- What's New
- Function Overview
- Product Bulletin
-
Service Overview
- GaussDB(DWS) Infographics
- What Is GaussDB(DWS)?
- Data Warehouse Types
- Data Warehouse Flavors
- Advantages
- Application Scenarios
- Functions
- Concepts
- Related Services
- Security
- GaussDB(DWS) Permissions Management
- GaussDB(DWS) Access
- Restrictions
- Technical Support
- Service Quotas
- GaussDB(DWS) Technical Specifications
-
Billing
- GaussDB(DWS) Billing Overview
- Billing Modes
- Item
- Billing Examples
- Billing Mode Change
- Renewal
- Bills
- Arrears
- Stopping Billing
- Cost Management
-
Billing FAQs
- How Can I Try Out GaussDB(DWS) for Free?
- Why Was I Deducted Fees After My GaussDB(DWS) Free Trial Expired?
- Why Can't I See a Cluster After I Subscribe to a Free GaussDB(DWS) Trial?
- Does Pay-per-Use Billing Stop When My Cluster Stops?
- Why Is the Purchase Button Unavailable When I Create a Cluster?
- How Do I Unfreeze a Cluster?
- Can I Freeze or Shut Down a GaussDB(DWS) Cluster to Stop Billing?
-
Getting Started
- Checkpoint Vehicle Analysis
- Supply Chain Requirement Analysis of a Company
- Operations Status Analysis of a Retail Department Store
- Creating a Time Series Table
- Best Practices of Hot and Cold Data Management
- Best Practices for Automatic Partition Management
- Creating a Cluster and Connecting to It
- Using CDM to Migrate MySQL Data to the GaussDB(DWS) Cluster
- Using DLI Flink Jobs to Write Kafka Data to GaussDB(DWS) in Real Time
- Basic SQL Operations
-
Database Quick Start
- Before You Start
- Creating and Managing Databases
- Planning a Storage Model
- Creating and Managing Tables
- Loading Sample Data
- Querying System Catalogs
- Creating and Managing Schemas
- Creating and Managing Partitioned Tables
- Creating and Managing Indexes
- Creating and Managing Views
- Creating and Managing Sequences
- Creating and Managing Scheduled Tasks
- Getting Started with Common Practices
-
User Guide
- Using GaussDB(DWS)
- Preparations
- Creating a GaussDB(DWS) Cluster
-
Connecting to a GaussDB(DWS) Cluster
- Overview
- Obtaining the Connection Address of a GaussDB(DWS) Cluster
- Using a Visualization Tool to Connect to a GaussDB(DWS) Cluster
- Using the CLI to Connect to a GaussDB(DWS) Cluster
-
Using a Third-Party Database Adapter for GaussDB(DWS) Cluster Connection
-
Using the JDBC and ODBC Drivers to Connect to a Cluster
- Development Specifications
- JDBC Version Description
- Downloading the JDBC or ODBC Driver
- Using JDBC to Connect to a Cluster
- Configuring JDBC to Connect to a Cluster (Load Balancing Mode)
- Configuring JDBC to Connect to a Cluster (IAM Authentication Mode)
- Third-party Connection Pool of the JDBC Configuration Database
- Using ODBC to Connect to a Cluster
- Using the Third-Party Function Library psycopg2 of Python to Connect to a Cluster
- Using the Python Library PyGreSQL to Connect to a Cluster
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Using the JDBC and ODBC Drivers to Connect to a Cluster
- Creating a GaussDB(DWS) Database and User
- Migrating Service Data to a GaussDB(DWS) Cluster
- GaussDB(DWS) Cluster Data Security and Encryption
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GaussDB(DWS) Cluster Management
- Viewing GaussDB(DWS) Cluster Details
- Checking the GaussDB(DWS) Cluster Status
- Viewing the GaussDB(DWS) Cluster Topology
- Managing GaussDB(DWS) Cluster Connections
- GaussDB(DWS) Resource Load Management
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Managing GaussDB(DWS) Logical Clusters
- Logical Cluster Overview
- Adding/Deleting a Logical Cluster
- Managing Logical Clusters
- Elastically Adding or Deleting a Logical Cluster
- Tutorial: Converting a Physical Cluster That Contains Data into a Logical Cluster
- Tutorial: Dividing a New Physical Cluster into Logical Clusters
- Tutorial: Setting a Read-Only Logical Cluster and Binding It to a User
- Modifying GUC Parameters of the GaussDB(DWS) Cluster
- Managing GaussDB(DWS) Tags
- Resetting the Password the GaussDB(DWS) Database Administrator
- Starting, Stopping, and Deleting a GaussDB(DWS) Cluster
- Managing Enterprise Projects
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GaussDB(DWS) Cluster O&M
- Viewing GaussDB(DWS) Cluster Monitoring Information on the Monitoring Panel (DMS)
- Viewing GaussDB(DWS) Cluster Monitoring Information on Cloud Eye
- Monitoring and Diagnosing Top SQL Statements in a GaussDB(DWS) Cluster
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Viewing GaussDB(DWS) Cluster Alarms
- Alarm Management
- Alarm Rules
- Alarm Subscriptions
-
Alarm Handling
- DWS_2000000001 Node CPU Usage Exceeds the Threshold
- DWS_2000000006 Node Data Disk Usage Exceeds the Threshold
- DWS_2000000009 Node Data Disk I/O Usage Exceeds the Threshold
- DWS_2000000012 Node Data Disk Latency Exceeds the Threshold
- DWS_2000000016 Data Spilled to Disks of the Query Statement Exceeds the Threshold
- DWS_2000000017 Number of Queuing Query Statements Exceeds the Threshold
- DWS_2000000018 Queue Congestion in the Default Cluster Resource Pool
- DWS_2000000020 Long SQL Probe Execution Duration in a Cluster
- DWS_2000000023 A Vacuum Full Operation That Holds a Lock for A Long Time Exists in the Cluster
- DWS_2000000027 Memory Usage of a GaussDB(DWS) Cluster Node Exceeds the Threshold
- DWS_2000000028 Dynamic Memory Usage of GaussDB(DWS) Cluster Nodes Exceeds the Threshold
- DWS_2000000029 Usage of a GaussDB(DWS) Cluster Resource Pool Exceeds the Threshold
- DWS_2000000030 Session Usage in a GaussDB(DWS) Cluster Exceeds the Threshold
- DWS_2000000031 Active Session Usage in a GaussDB(DWS) Cluster Exceeds the Threshold
- DWS_2000000032 Number of Database Deadlocks in a GaussDB(DWS) Cluster Exceeds the Threshold
- DWS_2000000033 GaussDB(DWS) Cluster Database Session Usage Exceeds the Threshold
- Viewing and Subscribing to GaussDB(DWS) Cluster Events
- Common O&M Commands of GaussDB(DWS)
- Backing Up and Restoring a GaussDB(DWS) Cluster
- Scaling GaussDB(DWS) Cluster Nodes
- Changing GaussDB(DWS) Cluster Specifications
- GaussDB(DWS) Cluster DR Management
- Upgrading a GaussDB(DWS) Cluster
- GaussDB(DWS) Cluster Log Management
- Handling Abnormal GaussDB(DWS) Clusters
- Reclaiming GaussDB(DWS) Space Using Vacuum
- Authorizing a GaussDB(DWS) Cluster O&M Account
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Best Practices
-
Import and Export
- Best Practices for DataImport
- GDS Practice Guide
- Migrating Data from OBS Buckets to a GaussDB(DWS) Cluster
- Using GDS to Import Table Data from a Remote Server to a GaussDB(DWS) Cluster
- Importing Table Data from MRS Hive to a GaussDB(DWS) Cluster
- Enabling Cross-Cluster Access of Hive Metastore Through an External Schema
- Importing Table Data from DLI to a GaussDB(DWS) Cluster
- Migrating Data Between GaussDB(DWS) Clusters Using Foreign Tables
- Exporting ORC Data from a GaussDB(DWS) Cluster to an MRS Cluster
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Data Migration
- Using CDM to Migrate Oracle Data to a GaussDB(DWS) Cluster
- Using CDM to Migrate MySQL Data to a GaussDB(DWS) Cluster
- Using DRS to Synchronize MySQL Table Data to a GaussDB(DWS) Cluster in Real Time
- Using a Flink Job of DLI to Synchronize Kafka Data to a GaussDB(DWS) Cluster in Real Time
- Using a Flink Job of DLI to Synchronize MySQL Data to a GaussDB(DWS) Cluster in Real Time
- Migrating Data Between GaussDB(DWS) Clusters Using GDS
- Data Analytics
- Decoupled Storage and Compute
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Data Development
- Cutting Costs by Switching Between Cold and Hot Data Storage in GaussDB(DWS)
- Cutting Partition Maintenance Costs for the E-commerce and IoT Industries by Leveraging GaussDB(DWS)'s Automatic Partition Management Feature
- Improving Development Efficiency by Leveraging GaussDB(DWS)'s View Decoupling and Rebuilding Function
- Best Practices for Using HStore Tables
- Best Practices of GIN Index
- Encrypting and Decrypting Data Columns
- Managing Data Permissions Through Views
- Database Management
-
Performance Tuning
-
Optimizing Table Structure Design to Enhance GaussDB(DWS) Query Performance
- Before Optimization: Learning Table Structure Design
- Step 1: Creating an Initial Table and Loading Sample Data
- Step 2: Testing System Performance of the Initial Table and Establishing a Baseline
- Step 3: Optimizing a Table
- Step 4: Creating Another Table and Loading Data
- Step 5: Testing System Performance in the New Table
- Step 6: Evaluating the Performance of the Optimized Table
- Appendix: Table Creation Syntax
- Analyzing SQL Statements That Are Being Executed to Handle GaussDB(DWS) Performance Issues
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Optimizing Table Structure Design to Enhance GaussDB(DWS) Query Performance
- Cluster Management
-
Import and Export
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Data Migration and Synchronization
- Data Migration to GaussDB(DWS)
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Importing Data
- Importing Data from OBS in Parallel
- Using GDS to Import Data from a Remote Server
- Importing Data from MRS to a Cluster
- Importing Data from One GaussDB(DWS) Cluster to Another
- GDS-based Cross-Cluster Interconnection
- Using Kettle to Import Data
- Using a gsql Meta-Command to Import Data
- Running the COPY FROM STDIN Statement to Import Data
- Full Database Migration
- Real-time Import
- Metadata Migration
- Exporting Data
- Other Operations
-
Developer Guide
-
Standard data warehouse (9.1.0.x)
- Before You Start
-
GaussDB(DWS) Development Design Proposal
- Overview
- GaussDB(DWS) Connection Management Specifications
- GaussDB(DWS) Object Design Specifications
- GaussDB(DWS) SQL Statement Development Specifications
- GaussDB(DWS) Stored Procedure Development Specifications
- Detailed Design Rules for GaussDB(DWS) Objects
-
Creating and Managing GaussDB(DWS) Database Objects
- Creating and Managing GaussDB(DWS) Databases
- Creating and Managing GaussDB(DWS) Schemas
- Creating and Managing GaussDB(DWS) Tables
- Selecting a GaussDB(DWS) Table Storage Model
- Creating and Managing GaussDB(DWS) Partitioned Tables
- Creating and Managing GaussDB(DWS) Indexes
- Creating and Using GaussDB(DWS) Sequences
- Creating and Managing GaussDB(DWS) Views
- Creating and Managing GaussDB(DWS) Scheduled Tasks
- Viewing GaussDB(DWS) System Catalogs
- Syntax Compatibility Differences Among Oracle, Teradata, and MySQL
- GaussDB(DWS) Database Security Management
- GaussDB(DWS) Data Query
- GaussDB(DWS) Sorting Rules
- GaussDB(DWS) User-Defined Functions
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GaussDB(DWS) Stored Procedure
- Overview
- Converting Data Types in GaussDB(DWS) Stored Procedures
- GaussDB(DWS) Stored Procedure Array and Record
- GaussDB(DWS) Stored Procedure Declaration Syntax
- Basic Statements of GaussDB(DWS) Stored Procedures
- Dynamic Statements of GaussDB(DWS) Stored Procedures
- GaussDB(DWS) Stored Procedure Control Statements
- Other Statements in a GaussDB(DWS) Stored Procedure
- GaussDB(DWS) Stored Procedure Cursor
- GaussDB(DWS) Stored Procedure Advanced Package
- GaussDB(DWS) Stored Procedure Debugging
- Using PostGIS Extension
- Using JDBC or ODBC for GaussDB(DWS) Secondary Development
- GaussDB(DWS) Resource Monitoring
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GaussDB(DWS) Performance Tuning
- Overview
- Performance Diagnosis
- System Optimization
-
SQL Tuning
- SQL Query Execution Process
- SQL Execution Plan
- Execution Plan Operator
- SQL Tuning Process
- Updating Statistics
- Reviewing and Modifying a Table Definition
- Advanced SQL Tuning
- Configuring Optimizer Parameters
- Hint-based Tuning
- Routinely Maintaining Tables
- Routinely Recreating an Index
- Automatic Retry upon SQL Statement Execution Errors
- Query Band Load Identification
-
SQL Tuning Examples
- Case: Selecting an Appropriate Distribution Column
- Case: Creating an Appropriate Index
- Case: Adding NOT NULL for JOIN Columns
- Case: Pushing Down Sort Operations to DNs
- Case: Configuring cost_param for Better Query Performance
- Case: Adjusting the Partial Clustering Key
- Case: Adjusting the Table Storage Mode in a Medium Table
- Case: Reconstructing Partition Tables
- Case: Adjusting the GUC Parameter best_agg_plan
- Case: Rewriting SQL Statements and Eliminating Prune Interference
- Case: Rewriting SQL Statements and Deleting in-clause
- Case: Setting Partial Cluster Keys
- Case: Converting from NOT IN to NOT EXISTS
-
GaussDB(DWS) System Catalogs and Views
- Overview of System Catalogs and System Views
-
System Catalogs
- GS_BLOCKLIST_QUERY
- GS_BLOCKLIST_SQL
- GS_OBSSCANINFO
- GS_RESPOOL_RESOURCE_HISTORY
- GS_WLM_INSTANCE_HISTORY
- GS_WLM_OPERATOR_INFO
- GS_WLM_SESSION_INFO
- GS_WLM_USER_RESOURCE_HISTORY
- PG_AGGREGATE
- PG_AM
- PG_AMOP
- PG_AMPROC
- PG_ATTRDEF
- PG_ATTRIBUTE
- PG_AUTHID
- PG_AUTH_HISTORY
- PG_AUTH_MEMBERS
- PG_BLOCKLISTS
- PG_CAST
- PG_CLASS
- PG_COLLATION
- PG_CONSTRAINT
- PG_CONVERSION
- PG_DATABASE
- PG_DB_ROLE_SETTING
- PG_DEFAULT_ACL
- PG_DEPEND
- PG_DESCRIPTION
- PG_ENUM
- PG_EXCEPT_RULE
- PG_EXTENSION
- PG_EXTENSION_DATA_SOURCE
- PG_FINE_DR_INFO
- PG_FOREIGN_DATA_WRAPPER
- PG_FOREIGN_SERVER
- PG_FOREIGN_TABLE
- PG_INDEX
- PG_INHERITS
- PG_JOB_INFO
- PG_JOBS
- PG_LANGUAGE
- PG_LARGEOBJECT
- PG_LARGEOBJECT_METADATA
- PG_MATVIEW
- PG_NAMESPACE
- PG_OBJECT
- PG_OBSSCANINFO
- PG_OPCLASS
- PG_OPERATOR
- PG_OPFAMILY
- PG_PARTITION
- PG_PLTEMPLATE
- PG_PROC
- PG_PUBLICATION
- PG_PUBLICATION_NAMESPACE
- PG_PUBLICATION_REL
- PG_RANGE
- PG_REDACTION_COLUMN
- PG_REDACTION_POLICY
- PG_RELFILENODE_SIZE
- PG_RLSPOLICY
- PG_RESOURCE_POOL
- PG_REWRITE
- PG_SECLABEL
- PG_SHDEPEND
- PG_SHDESCRIPTION
- PG_SHSECLABEL
- PG_STATISTIC
- PG_STATISTIC_EXT
- PG_STAT_OBJECT
- PG_SUBSCRIPTION
- PG_SYNONYM
- PG_TABLESPACE
- PG_TRIGGER
- PG_TS_CONFIG
- PG_TS_CONFIG_MAP
- PG_TS_DICT
- PG_TS_PARSER
- PG_TS_TEMPLATE
- PG_TYPE
- PG_USER_MAPPING
- PG_USER_STATUS
- PG_WORKLOAD_ACTION
- PGXC_CLASS
- PGXC_GROUP
- PGXC_NODE
- PLAN_TABLE_DATA
- SNAPSHOT
- TABLES_SNAP_TIMESTAMP
- System Catalogs for Performance View Snapshot
-
System Views
- ALL_ALL_TABLES
- ALL_CONSTRAINTS
- ALL_CONS_COLUMNS
- ALL_COL_COMMENTS
- ALL_DEPENDENCIES
- ALL_IND_COLUMNS
- ALL_IND_EXPRESSIONS
- ALL_INDEXES
- ALL_OBJECTS
- ALL_PROCEDURES
- ALL_SEQUENCES
- ALL_SOURCE
- ALL_SYNONYMS
- ALL_TAB_COLUMNS
- ALL_TAB_COMMENTS
- ALL_TABLES
- ALL_USERS
- ALL_VIEWS
- DBA_DATA_FILES
- DBA_USERS
- DBA_COL_COMMENTS
- DBA_CONSTRAINTS
- DBA_CONS_COLUMNS
- DBA_IND_COLUMNS
- DBA_IND_EXPRESSIONS
- DBA_IND_PARTITIONS
- DBA_INDEXES
- DBA_OBJECTS
- DBA_PART_INDEXES
- DBA_PART_TABLES
- DBA_PROCEDURES
- DBA_SEQUENCES
- DBA_SOURCE
- DBA_SYNONYMS
- DBA_TAB_COLUMNS
- DBA_TAB_COMMENTS
- DBA_TAB_PARTITIONS
- DBA_TABLES
- DBA_TABLESPACES
- DBA_TRIGGERS
- DBA_VIEWS
- DUAL
- GET_ALL_TSC_INFO
- GET_TSC_INFO
- GLOBAL_COLUMN_TABLE_IO_STAT
- GLOBAL_REDO_STAT
- GLOBAL_REL_IOSTAT
- GLOBAL_ROW_TABLE_IO_STAT
- GLOBAL_STAT_DATABASE
- GLOBAL_TABLE_CHANGE_STAT
- GLOBAL_TABLE_STAT
- GLOBAL_WORKLOAD_SQL_COUNT
- GLOBAL_WORKLOAD_SQL_ELAPSE_TIME
- GLOBAL_WORKLOAD_TRANSACTION
- GS_ALL_CONTROL_GROUP_INFO
- GS_BLOCKLIST_QUERY
- GS_BLOCKLIST_SQL
- GS_CLUSTER_RESOURCE_INFO
- GS_COLUMN_TABLE_IO_STAT
- GS_OBS_READ_TRAFFIC
- GS_OBS_WRITE_TRAFFIC
- GS_INSTR_UNIQUE_SQL
- GS_NODE_STAT_RESET_TIME
- GS_OBS_LATENCY
- GS_QUERY_MONITOR
- GS_QUERY_RESOURCE_INFO
- GS_REL_IOSTAT
- GS_RESPOOL_RUNTIME_INFO
- GS_RESPOOL_RESOURCE_INFO
- GS_RESPOOL_MONITOR
- GS_ROW_TABLE_IO_STAT
- GS_SESSION_CPU_STATISTICS
- GS_SESSION_MEMORY_STATISTICS
- GS_SQL_COUNT
- GS_STAT_DB_CU
- GS_STAT_SESSION_CU
- GS_TABLE_CHANGE_STAT
- GS_TABLE_STAT
- GS_TOTAL_NODEGROUP_MEMORY_DETAIL
- GS_USER_MONITOR
- GS_USER_TRANSACTION
- GS_VIEW_DEPENDENCY
- GS_VIEW_DEPENDENCY_PATH
- GS_VIEW_INVALID
- GS_WAIT_EVENTS
- GS_WLM_OPERAROR_INFO
- GS_WLM_OPERATOR_HISTORY
- GS_WLM_OPERATOR_STATISTICS
- GS_WLM_SESSION_INFO
- GS_WLM_SESSION_HISTORY
- GS_WLM_SESSION_STATISTICS
- GS_WLM_SQL_ALLOW
- GS_WORKLOAD_SQL_COUNT
- GS_WORKLOAD_SQL_ELAPSE_TIME
- GS_WORKLOAD_TRANSACTION
- MPP_TABLES
- PG_AVAILABLE_EXTENSION_VERSIONS
- PG_AVAILABLE_EXTENSIONS
- PG_BULKLOAD_STATISTICS
- PG_COMM_CLIENT_INFO
- PG_COMM_DELAY
- PG_COMM_STATUS
- PG_COMM_RECV_STREAM
- PG_COMM_SEND_STREAM
- PG_COMM_QUERY_SPEED
- PG_CONTROL_GROUP_CONFIG
- PG_CURSORS
- PG_EXT_STATS
- PG_GET_INVALID_BACKENDS
- PG_GET_SENDERS_CATCHUP_TIME
- PG_GROUP
- PG_INDEXES
- PG_JOB
- PG_JOB_PROC
- PG_JOB_SINGLE
- PG_LIFECYCLE_DATA_DISTRIBUTE
- PG_LOCKS
- PG_LWLOCKS
- PG_NODE_ENV
- PG_OS_THREADS
- PG_POOLER_STATUS
- PG_PREPARED_STATEMENTS
- PG_PREPARED_XACTS
- PG_PUBLICATION_TABLES
- PG_QUERYBAND_ACTION
- PG_REPLICATION_SLOTS
- PG_ROLES
- PG_RULES
- PG_RUNNING_XACTS
- PG_SECLABELS
- PG_SEQUENCES
- PG_SESSION_WLMSTAT
- PG_SESSION_IOSTAT
- PG_SETTINGS
- PG_SHADOW
- PG_SHARED_MEMORY_DETAIL
- PG_STATS
- PG_STAT_ACTIVITY
- PG_STAT_ALL_INDEXES
- PG_STAT_ALL_TABLES
- PG_STAT_BAD_BLOCK
- PG_STAT_BGWRITER
- PG_STAT_DATABASE
- PG_STAT_DATABASE_CONFLICTS
- PG_STAT_GET_MEM_MBYTES_RESERVED
- PG_STAT_USER_FUNCTIONS
- PG_STAT_USER_INDEXES
- PG_STAT_USER_TABLES
- PG_STAT_REPLICATION
- PG_STAT_SYS_INDEXES
- PG_STAT_SYS_TABLES
- PG_STAT_XACT_ALL_TABLES
- PG_STAT_XACT_SYS_TABLES
- PG_STAT_XACT_USER_FUNCTIONS
- PG_STAT_XACT_USER_TABLES
- PG_STATIO_ALL_INDEXES
- PG_STATIO_ALL_SEQUENCES
- PG_STATIO_ALL_TABLES
- PG_STATIO_SYS_INDEXES
- PG_STATIO_SYS_SEQUENCES
- PG_STATIO_SYS_TABLES
- PG_STATIO_USER_INDEXES
- PG_STATIO_USER_SEQUENCES
- PG_STATIO_USER_TABLES
- PG_THREAD_WAIT_STATUS
- PG_TABLES
- PG_TDE_INFO
- PG_TIMEZONE_ABBREVS
- PG_TIMEZONE_NAMES
- PG_TOTAL_MEMORY_DETAIL
- PG_TOTAL_SCHEMA_INFO
- PG_TOTAL_USER_RESOURCE_INFO
- PG_USER
- PG_USER_MAPPINGS
- PG_VIEWS
- PG_WLM_STATISTICS
- PGXC_AIO_RESOURCE_POOL_STATS
- PGXC_BULKLOAD_PROGRESS
- PGXC_BULKLOAD_INFO
- PGXC_BULKLOAD_STATISTICS
- PGXC_COLUMN_TABLE_IO_STAT
- PGXC_COMM_CLIENT_INFO
- PGXC_COMM_DELAY
- PGXC_COMM_RECV_STREAM
- PGXC_COMM_SEND_STREAM
- PGXC_COMM_STATUS
- PGXC_COMM_QUERY_SPEED
- PGXC_DEADLOCK
- PGXC_DISK_CACHE_STATS
- PGXC_DISK_CACHE_ALL_STATS
- PGXC_DISK_CACHE_PATH_INFO
- PGXC_GET_STAT_ALL_TABLES
- PGXC_GET_STAT_ALL_PARTITIONS
- PGXC_GET_TABLE_SKEWNESS
- PGXC_GTM_SNAPSHOT_STATUS
- PGXC_INSTANCE_TIME
- PGXC_LOCKWAIT_DETAIL
- PGXC_INSTR_UNIQUE_SQL
- PGXC_LOCK_CONFLICTS
- PGXC_LWLOCKS
- PGXC_MEMORY_DEBUG_INFO
- PGXC_NODE_ENV
- PGXC_NODE_STAT_RESET_TIME
- PGXC_OBS_IO_SCHEDULER_STATS
- PGXC_OBS_IO_SCHEDULER_PERIODIC_STATS
- PGXC_OS_RUN_INFO
- PGXC_OS_THREADS
- PGXC_POOLER_STATUS
- PGXC_PREPARED_XACTS
- PGXC_REDO_STAT
- PGXC_REL_IOSTAT
- PGXC_REPLICATION_SLOTS
- PGXC_RESPOOL_RUNTIME_INFO
- PGXC_RESPOOL_RESOURCE_INFO
- PGXC_RESPOOL_RESOURCE_HISTORY
- PGXC_ROW_TABLE_IO_STAT
- PGXC_RUNNING_XACTS
- PGXC_SETTINGS
- PGXC_SESSION_WLMSTAT
- PGXC_STAT_ACTIVITY
- PGXC_STAT_BAD_BLOCK
- PGXC_STAT_BGWRITER
- PGXC_STAT_DATABASE
- PGXC_STAT_OBJECT
- PGXC_STAT_REPLICATION
- PGXC_STAT_TABLE_DIRTY
- PGXC_STAT_WAL
- PGXC_SQL_COUNT
- PGXC_TABLE_CHANGE_STAT
- PGXC_TABLE_STAT
- PGXC_THREAD_WAIT_STATUS
- PGXC_TOTAL_MEMORY_DETAIL
- PGXC_TOTAL_SCHEMA_INFO
- PGXC_TOTAL_SCHEMA_INFO_ANALYZE
- PGXC_TOTAL_USER_RESOURCE_INFO
- PGXC_USER_TRANSACTION
- PGXC_VARIABLE_INFO
- PGXC_WAIT_DETAIL
- PGXC_WAIT_EVENTS
- PGXC_WLM_OPERATOR_HISTORY
- PGXC_WLM_OPERATOR_INFO
- PGXC_WLM_OPERATOR_STATISTICS
- PGXC_WLM_SESSION_INFO
- PGXC_WLM_SESSION_HISTORY
- PGXC_WLM_SESSION_STATISTICS
- PGXC_WLM_TABLE_DISTRIBUTION_SKEWNESS
- PGXC_WLM_USER_RESOURCE_HISTORY
- PGXC_WLM_WORKLOAD_RECORDS
- PGXC_WORKLOAD_SQL_COUNT
- PGXC_WORKLOAD_SQL_ELAPSE_TIME
- PGXC_WORKLOAD_TRANSACTION
- PLAN_TABLE
- PV_FILE_STAT
- PV_INSTANCE_TIME
- PV_MATVIEW_DETAIL
- PV_OS_RUN_INFO
- PV_SESSION_MEMORY
- PV_SESSION_MEMORY_DETAIL
- PV_SESSION_STAT
- PV_SESSION_TIME
- PV_TOTAL_MEMORY_DETAIL
- PV_REDO_STAT
- PV_RUNTIME_ATTSTATS
- PV_RUNTIME_RELSTATS
- REDACTION_COLUMNS
- REDACTION_POLICIES
- REMOTE_TABLE_STAT
- SHOW_TSC_INFO
- SHOW_ALL_TSC_INFO
- USER_COL_COMMENTS
- USER_CONSTRAINTS
- USER_CONS_COLUMNS
- USER_INDEXES
- USER_IND_COLUMNS
- USER_IND_EXPRESSIONS
- USER_IND_PARTITIONS
- USER_JOBS
- USER_OBJECTS
- USER_PART_INDEXES
- USER_PART_TABLES
- USER_PROCEDURES
- USER_SEQUENCES
- USER_SOURCE
- USER_SYNONYMS
- USER_TAB_COLUMNS
- USER_TAB_COMMENTS
- USER_TAB_PARTITIONS
- USER_TABLES
- USER_TRIGGERS
- USER_VIEWS
- V$SESSION
- V$SESSION_LONGOPS
-
GUC Parameters of the GaussDB(DWS) Database
- Viewing GUC Parameters
- Configuring GUC Parameters
- GUC Parameter Usage
- Connection and Authentication
- Resource Consumption
- Parallel Data Import
- Write Ahead Logs
- HA Replication
- Query Planning
- Error Reporting and Logging
- Alarm Detection
- Statistics During the Database Running
- Resource Management
- Automatic Cleanup
- Default Settings of Client Connection
- Lock Management
- Version and Platform Compatibility
- Fault Tolerance
- Connection Pool Parameters
- Cluster Transaction Parameters
- Developer Operations
- Auditing
- Transaction Monitoring
- GTM Parameters
- Miscellaneous Parameters
- GaussDB(DWS) Developer Terms
-
Standard data warehouse (8.1.3.x)
- Before You Start
-
GaussDB(DWS) Development Design Specifications
- Overview
- GaussDB(DWS) Connection Management Specifications
- GaussDB(DWS) Object Design Specifications
- GaussDB(DWS) SQL Statement Development Specifications
- GaussDB(DWS) Stored Procedure Development Specifications
- Detailed Design Rules for GaussDB(DWS) Objects
-
Creating and Managing GaussDB(DWS) Database Objects
- Creating and Managing GaussDB(DWS) Databases
- Creating and Managing GaussDB(DWS) Schemas
- Selecting a GaussDB(DWS) Table Storage Model
- Creating and Managing GaussDB(DWS) Tables
- Creating and Managing GaussDB(DWS) Partitioned Tables
- Creating and Managing GaussDB(DWS) Indexes
- Creating and Using GaussDB(DWS) Sequences
- Creating and Managing GaussDB(DWS) Views
- Creating and Managing GaussDB(DWS) Scheduled Tasks
- Viewing GaussDB(DWS) System Catalogs
- Syntax Compatibility Differences Among Oracle, Teradata, and MySQL
- GaussDB(DWS) Database Security Management
- GaussDB(DWS) Data Query
- GaussDB(DWS) Sorting Rules
- GaussDB(DWS) User-Defined Functions
-
GaussDB(DWS) Stored Procedure
- Overview
- Converting Data Types in GaussDB(DWS) Stored Procedures
- GaussDB(DWS) Stored Procedure Array and Record
- GaussDB(DWS) Stored Procedure Declaration Syntax
- Basic Statements of GaussDB(DWS) Stored Procedures
- Dynamic Statements of GaussDB(DWS) Stored Procedures
- GaussDB(DWS) Stored Procedure Control Statements
- Other Statements in a GaussDB(DWS) Stored Procedure
- GaussDB(DWS) Stored Procedure Cursor
- GaussDB(DWS) Stored Procedure Advanced Package
- GaussDB(DWS) Stored Procedure Debugging
- Using PostGIS Extension
- Using JDBC or ODBC for GaussDB(DWS) Secondary Development
- GaussDB(DWS) Resource Monitoring
-
GaussDB(DWS) Performance Tuning
- Overview
- Performance Diagnosis
- System Optimization
-
SQL Tuning
- SQL Query Execution Process
- SQL Execution Plan
- Execution Plan Operator
- SQL Tuning Process
- Updating Statistics
- Reviewing and Modifying a Table Definition
- Advanced SQL Tuning
- Hint-based Tuning
- Routinely Maintaining Tables
- Routinely Recreating an Index
- Automatic Retry upon SQL Statement Execution Errors
- query_band Load Identification
-
SQL Tuning Examples
- Case: Selecting an Appropriate Distribution Column
- Case: Creating an Appropriate Index
- Case: Adding NOT NULL for JOIN Columns
- Case: Pushing Down Sort Operations to DNs
- Case: Configuring cost_param for Better Query Performance
- Case: Adjusting the Partial Clustering Key
- Case: Adjusting the Table Storage Mode in a Medium Table
- Case: Reconstructing Partition Tables
- Case: Adjusting the GUC Parameter best_agg_plan
- Case: Rewriting SQL Statements and Eliminating Prune Interference
- Case: Rewriting SQL Statements and Deleting in-clause
- Case: Setting Partial Cluster Keys
- Case: Converting from NOT IN to NOT EXISTS
-
GaussDB(DWS) System Catalogs and Views
- Overview of System Catalogs and System Views
-
System Catalogs
- GS_OBSSCANINFO
- GS_RESPOOL_RESOURCE_HISTORY
- GS_WLM_INSTANCE_HISTORY
- GS_WLM_OPERATOR_INFO
- GS_WLM_SESSION_INFO
- GS_WLM_USER_RESOURCE_HISTORY
- PG_AGGREGATE
- PG_AM
- PG_AMOP
- PG_AMPROC
- PG_ATTRDEF
- PG_ATTRIBUTE
- PG_AUTHID
- PG_AUTH_HISTORY
- PG_AUTH_MEMBERS
- PG_CAST
- PG_CLASS
- PG_COLLATION
- PG_CONSTRAINT
- PG_CONVERSION
- PG_DATABASE
- PG_DB_ROLE_SETTING
- PG_DEFAULT_ACL
- PG_DEPEND
- PG_DESCRIPTION
- PG_ENUM
- PG_EXTENSION
- PG_EXTENSION_DATA_SOURCE
- PG_FOREIGN_DATA_WRAPPER
- PG_FOREIGN_SERVER
- PG_FOREIGN_TABLE
- PG_INDEX
- PG_INHERITS
- PG_JOBS
- PG_LANGUAGE
- PG_LARGEOBJECT
- PG_LARGEOBJECT_METADATA
- PG_NAMESPACE
- PG_OBJECT
- PG_OBSSCANINFO
- PG_OPCLASS
- PG_OPERATOR
- PG_OPFAMILY
- PG_PARTITION
- PG_PLTEMPLATE
- PG_PROC
- PG_RANGE
- PG_REDACTION_COLUMN
- PG_REDACTION_POLICY
- PG_RELFILENODE_SIZE
- PG_RLSPOLICY
- PG_RESOURCE_POOL
- PG_REWRITE
- PG_SECLABEL
- PG_SHDEPEND
- PG_SHDESCRIPTION
- PG_SHSECLABEL
- PG_STATISTIC
- PG_STATISTIC_EXT
- PG_SYNONYM
- PG_TABLESPACE
- PG_TRIGGER
- PG_TS_CONFIG
- PG_TS_CONFIG_MAP
- PG_TS_DICT
- PG_TS_PARSER
- PG_TS_TEMPLATE
- PG_TYPE
- PG_USER_MAPPING
- PG_USER_STATUS
- PG_WORKLOAD_ACTION
- PGXC_CLASS
- PGXC_GROUP
- PGXC_NODE
- PLAN_TABLE_DATA
- SNAPSHOT
- TABLES_SNAP_TIMESTAMP
- System Catalogs for Performance View Snapshot
-
System Views
- ALL_ALL_TABLES
- ALL_CONSTRAINTS
- ALL_CONS_COLUMNS
- ALL_COL_COMMENTS
- ALL_DEPENDENCIES
- ALL_IND_COLUMNS
- ALL_IND_EXPRESSIONS
- ALL_INDEXES
- ALL_OBJECTS
- ALL_PROCEDURES
- ALL_SEQUENCES
- ALL_SOURCE
- ALL_SYNONYMS
- ALL_TAB_COLUMNS
- ALL_TAB_COMMENTS
- ALL_TABLES
- ALL_USERS
- ALL_VIEWS
- DBA_DATA_FILES
- DBA_USERS
- DBA_COL_COMMENTS
- DBA_CONSTRAINTS
- DBA_CONS_COLUMNS
- DBA_IND_COLUMNS
- DBA_IND_EXPRESSIONS
- DBA_IND_PARTITIONS
- DBA_INDEXES
- DBA_OBJECTS
- DBA_PART_INDEXES
- DBA_PART_TABLES
- DBA_PROCEDURES
- DBA_SEQUENCES
- DBA_SOURCE
- DBA_SYNONYMS
- DBA_TAB_COLUMNS
- DBA_TAB_COMMENTS
- DBA_TAB_PARTITIONS
- DBA_TABLES
- DBA_TABLESPACES
- DBA_TRIGGERS
- DBA_VIEWS
- DUAL
- GLOBAL_COLUMN_TABLE_IO_STAT
- GLOBAL_REDO_STAT
- GLOBAL_REL_IOSTAT
- GLOBAL_ROW_TABLE_IO_STAT
- GLOBAL_STAT_DATABASE
- GLOBAL_TABLE_CHANGE_STAT
- GLOBAL_TABLE_STAT
- GLOBAL_WORKLOAD_SQL_COUNT
- GLOBAL_WORKLOAD_SQL_ELAPSE_TIME
- GLOBAL_WORKLOAD_TRANSACTION
- GS_ALL_CONTROL_GROUP_INFO
- GS_CLUSTER_RESOURCE_INFO
- GS_COLUMN_TABLE_IO_STAT
- GS_INSTR_UNIQUE_SQL
- GS_NODE_STAT_RESET_TIME
- GS_REL_IOSTAT
- GS_RESPOOL_RUNTIME_INFO
- GS_RESPOOL_RESOURCE_INFO
- GS_ROW_TABLE_IO_STAT
- GS_SESSION_CPU_STATISTICS
- GS_SESSION_MEMORY_STATISTICS
- GS_SQL_COUNT
- GS_STAT_DB_CU
- GS_STAT_SESSION_CU
- GS_TABLE_CHANGE_STAT
- GS_TABLE_STAT
- GS_TOTAL_NODEGROUP_MEMORY_DETAIL
- GS_USER_TRANSACTION
- GS_VIEW_DEPENDENCY
- GS_VIEW_DEPENDENCY_PATH
- GS_VIEW_INVALID
- GS_WAIT_EVENTS
- GS_WLM_OPERAROR_INFO
- GS_WLM_OPERATOR_HISTORY
- GS_WLM_OPERATOR_STATISTICS
- GS_WLM_SESSION_INFO
- GS_WLM_SESSION_HISTORY
- GS_WLM_SESSION_STATISTICS
- GS_WLM_SQL_ALLOW
- GS_WORKLOAD_SQL_COUNT
- GS_WORKLOAD_SQL_ELAPSE_TIME
- GS_WORKLOAD_TRANSACTION
- MPP_TABLES
- PG_AVAILABLE_EXTENSION_VERSIONS
- PG_AVAILABLE_EXTENSIONS
- PG_BULKLOAD_STATISTICS
- PG_COMM_CLIENT_INFO
- PG_COMM_DELAY
- PG_COMM_STATUS
- PG_COMM_RECV_STREAM
- PG_COMM_SEND_STREAM
- PG_COMM_QUERY_SPEED
- PG_CONTROL_GROUP_CONFIG
- PG_CURSORS
- PG_EXT_STATS
- PG_GET_INVALID_BACKENDS
- PG_GET_SENDERS_CATCHUP_TIME
- PG_GROUP
- PG_INDEXES
- PG_JOB
- PG_JOB_PROC
- PG_JOB_SINGLE
- PG_LIFECYCLE_DATA_DISTRIBUTE
- PG_LOCKS
- PG_NODE_ENV
- PG_OS_THREADS
- PG_POOLER_STATUS
- PG_PREPARED_STATEMENTS
- PG_PREPARED_XACTS
- PG_QUERYBAND_ACTION
- PG_REPLICATION_SLOTS
- PG_ROLES
- PG_RULES
- PG_RUNNING_XACTS
- PG_SECLABELS
- PG_SESSION_WLMSTAT
- PG_SESSION_IOSTAT
- PG_SETTINGS
- PG_SHADOW
- PG_SHARED_MEMORY_DETAIL
- PG_STATS
- PG_STAT_ACTIVITY
- PG_STAT_ALL_INDEXES
- PG_STAT_ALL_TABLES
- PG_STAT_BAD_BLOCK
- PG_STAT_BGWRITER
- PG_STAT_DATABASE
- PG_STAT_DATABASE_CONFLICTS
- PG_STAT_GET_MEM_MBYTES_RESERVED
- PG_STAT_USER_FUNCTIONS
- PG_STAT_USER_INDEXES
- PG_STAT_USER_TABLES
- PG_STAT_REPLICATION
- PG_STAT_SYS_INDEXES
- PG_STAT_SYS_TABLES
- PG_STAT_XACT_ALL_TABLES
- PG_STAT_XACT_SYS_TABLES
- PG_STAT_XACT_USER_FUNCTIONS
- PG_STAT_XACT_USER_TABLES
- PG_STATIO_ALL_INDEXES
- PG_STATIO_ALL_SEQUENCES
- PG_STATIO_ALL_TABLES
- PG_STATIO_SYS_INDEXES
- PG_STATIO_SYS_SEQUENCES
- PG_STATIO_SYS_TABLES
- PG_STATIO_USER_INDEXES
- PG_STATIO_USER_SEQUENCES
- PG_STATIO_USER_TABLES
- PG_THREAD_WAIT_STATUS
- PG_TABLES
- PG_TDE_INFO
- PG_TIMEZONE_ABBREVS
- PG_TIMEZONE_NAMES
- PG_TOTAL_MEMORY_DETAIL
- PG_TOTAL_SCHEMA_INFO
- PG_TOTAL_USER_RESOURCE_INFO
- PG_USER
- PG_USER_MAPPINGS
- PG_VIEWS
- PG_WLM_STATISTICS
- PGXC_BULKLOAD_PROGRESS
- PGXC_BULKLOAD_STATISTICS
- PGXC_COLUMN_TABLE_IO_STAT
- PGXC_COMM_CLIENT_INFO
- PGXC_COMM_DELAY
- PGXC_COMM_RECV_STREAM
- PGXC_COMM_SEND_STREAM
- PGXC_COMM_STATUS
- PGXC_COMM_QUERY_SPEED
- PGXC_DEADLOCK
- PGXC_GET_STAT_ALL_TABLES
- PGXC_GET_STAT_ALL_PARTITIONS
- PGXC_GET_TABLE_SKEWNESS
- PGXC_GTM_SNAPSHOT_STATUS
- PGXC_INSTANCE_TIME
- PGXC_LOCKWAIT_DETAIL
- PGXC_INSTR_UNIQUE_SQL
- PGXC_LOCK_CONFLICTS
- PGXC_NODE_ENV
- PGXC_NODE_STAT_RESET_TIME
- PGXC_OS_RUN_INFO
- PGXC_OS_THREADS
- PGXC_PREPARED_XACTS
- PGXC_REDO_STAT
- PGXC_REL_IOSTAT
- PGXC_REPLICATION_SLOTS
- PGXC_RESPOOL_RUNTIME_INFO
- PGXC_RESPOOL_RESOURCE_INFO
- PGXC_RESPOOL_RESOURCE_HISTORY
- PGXC_ROW_TABLE_IO_STAT
- PGXC_RUNNING_XACTS
- PGXC_SETTINGS
- PGXC_SESSION_WLMSTAT
- PGXC_STAT_ACTIVITY
- PGXC_STAT_BAD_BLOCK
- PGXC_STAT_BGWRITER
- PGXC_STAT_DATABASE
- PGXC_STAT_REPLICATION
- PGXC_STAT_TABLE_DIRTY
- PGXC_SQL_COUNT
- PGXC_TABLE_CHANGE_STAT
- PGXC_TABLE_STAT
- PGXC_THREAD_WAIT_STATUS
- PGXC_TOTAL_MEMORY_DETAIL
- PGXC_TOTAL_SCHEMA_INFO
- PGXC_TOTAL_SCHEMA_INFO_ANALYZE
- PGXC_USER_TRANSACTION
- PGXC_VARIABLE_INFO
- PGXC_WAIT_DETAIL
- PGXC_WAIT_EVENTS
- PGXC_WLM_OPERATOR_HISTORY
- PGXC_WLM_OPERATOR_INFO
- PGXC_WLM_OPERATOR_STATISTICS
- PGXC_WLM_SESSION_INFO
- PGXC_WLM_SESSION_HISTORY
- PGXC_WLM_SESSION_STATISTICS
- PGXC_WLM_WORKLOAD_RECORDS
- PGXC_WORKLOAD_SQL_COUNT
- PGXC_WORKLOAD_SQL_ELAPSE_TIME
- PGXC_WORKLOAD_TRANSACTION
- PLAN_TABLE
- PV_FILE_STAT
- PV_INSTANCE_TIME
- PV_OS_RUN_INFO
- PV_SESSION_MEMORY
- PV_SESSION_MEMORY_DETAIL
- PV_SESSION_STAT
- PV_SESSION_TIME
- PV_TOTAL_MEMORY_DETAIL
- PV_REDO_STAT
- REDACTION_COLUMNS
- REDACTION_POLICIES
- REMOTE_TABLE_STAT
- USER_COL_COMMENTS
- USER_CONSTRAINTS
- USER_CONS_COLUMNS
- USER_INDEXES
- USER_IND_COLUMNS
- USER_IND_EXPRESSIONS
- USER_IND_PARTITIONS
- USER_JOBS
- USER_OBJECTS
- USER_PART_INDEXES
- USER_PART_TABLES
- USER_PROCEDURES
- USER_SEQUENCES
- USER_SOURCE
- USER_SYNONYMS
- USER_TAB_COLUMNS
- USER_TAB_COMMENTS
- USER_TAB_PARTITIONS
- USER_TABLES
- USER_TRIGGERS
- USER_VIEWS
- V$SESSION
- V$SESSION_LONGOPS
-
GUC Parameters of the GaussDB(DWS) Database
- Viewing GUC Parameters
- Configuring GUC Parameters
- GUC Parameter Usage
- Connection and Authentication
- Resource Consumption
- Parallel Data Import
- Write Ahead Logs
- HA Replication
- Query Planning
- Error Reporting and Logging
- Alarm Detection
- Statistics During the Database Running
- Resource Management
- Automatic Cleanup
- Default Settings of Client Connection
- Lock Management
- Version and Platform Compatibility
- Fault Tolerance
- Connection Pool Parameters
- Cluster Transaction Parameters
- Developer Operations
- Auditing
- Transaction Monitoring
- GTM Parameters
- Miscellaneous Parameters
- GaussDB(DWS) Developer Terms
- Hybrid Data Warehouse (9.1.0.x)
- Hybrid Data Warehouse (8.1.3.x)
- Historical Versions
-
Standard data warehouse (9.1.0.x)
-
SQL Syntax Reference
-
SQL Syntax Reference (9.1.0.x)
- GaussDB(DWS) SQL Overview
- Differences Between GaussDB(DWS) and PostgreSQL
- Keyword
-
Data Types
- Numeric Types
- Monetary Types
- Boolean Type
- Character Types
- Binary Data Types
- Date/Time Types
- Geometric Types
- Array
- Enumeration Type
- Network Address Types
- Bit String Types
- Text Search Types
- UUID Type
- JSON Types
- RoaringBitmap
- HLL Data Types
- Object Identifier Types
- Pseudo-Types
- Range Types
- Composite Types
- Data Types Supported by Column-Store Tables
- XML
- Constant and Macro
-
Functions and Operators
- Character Processing Functions and Operators
- Binary String Functions and Operators
- Bit String Functions and Operators
- Numeric Functions and Operators
- Date and Time Processing Functions and Operators
- SEQUENCE Functions
- Array Functions and Operators
- Logical Operators
- Comparison Operators
- Pattern Matching Operators
- Aggregate Functions
- Window Functions
- Type Conversion Functions
- JSON/JSONB Functions and Operators
- Security Functions
- Conditional Expression Functions
- Range Functions and Operators
- Data Redaction Functions
- Bitmap Functions and Operators
- UUID Functions
- Text Search Functions and Operators
- HLL Functions and Operators
- Set Returning Functions
- Geometric Functions and Operators
- Network Address Functions and Operators
- System Information Functions
- System Administration Functions
- Backup and Restoration Control Functions
- Database Object Functions
- Residual File Management Functions
- Statistics Information Functions
- Trigger Functions
- XML Functions
- Call Stack Recording Functions
- Hudi System Functions
- Funnel and Retention Functions
- EXTERNAL SCHEMA System Functions
- Storage-Compute Decoupling Functions
- Expressions
- Type Conversion
- Full Text Search
- System Operation
- Transaction Management
-
DDL Syntax
- DDL Syntax Overview
- ALTER BLOCK RULE
- ALTER DATABASE
- ALTER EXCEPT RULE
- ALTER EXTERNAL SCHEMA
- ALTER FOREIGN TABLE (GDS Import and Export)
- ALTER FOREIGN TABLE (for HDFS or OBS)
- ALTER FOREIGN TABLE (SQL on other GaussDB(DWS))
- ALTER FUNCTION
- ALTER GROUP
- ALTER INDEX
- ALTER LARGE OBJECT
- ALTER MATERIALIZED VIEW
- ALTER PUBLICATION
- ALTER REDACTION POLICY
- ALTER RESOURCE POOL
- ALTER ROLE
- ALTER SUBSCRIPTION
- ALTER ROW LEVEL SECURITY POLICY
- ALTER SCHEMA
- ALTER SEQUENCE
- ALTER SERVER
- ALTER SESSION
- ALTER SYNONYM
- ALTER SYSTEM KILL SESSION
- ALTER TABLE
- ALTER TABLE PARTITION
- ALTER TEXT SEARCH CONFIGURATION
- ALTER TEXT SEARCH DICTIONARY
- ALTER TRIGGER
- ALTER TYPE
- ALTER USER
- ALTER VIEW
- CLEAN CONNECTION
- CLOSE
- CLUSTER
- COMMENT
- CREATE BARRIER
- CREATE BLOCK RULE
- CREATE DATABASE
- CREATE EXCEPT RULE
- CREATE EXTERNAL SCHEMA
- CREATE FOREIGN TABLE (for GDS Import and Export)
- CREATE FOREIGN TABLE (SQL on OBS or Hadoop)
- CREATE FOREIGN TABLE (for OBS Import and Export)
- CREATE FOREIGN TABLE (SQL on other GaussDB(DWS))
- CREATE FUNCTION
- CREATE GROUP
- CREATE INDEX
- CREATE MATERIALIZED VIEW
- CREATE PROCEDURE
- CREATE PUBLICATION
- CREATE REDACTION POLICY
- CREATE ROW LEVEL SECURITY POLICY
- CREATE RESOURCE POOL
- CREATE ROLE
- CREATE SCHEMA
- CREATE SEQUENCE
- CREATE SERVER
- CREATE SUBSCRIPTION
- CREATE SYNONYM
- CREATE TABLE
- CREATE TABLE AS
- CREATE TABLE PARTITION
- CREATE TEXT SEARCH CONFIGURATION
- CREATE TEXT SEARCH DICTIONARY
- CREATE TRIGGER
- CREATE TYPE
- CREATE USER
- CREATE VIEW
- CURSOR
- DISCARD
- DROP BLOCK RULE
- DROP DATABASE
- DROP EXCEPT RULE
- DROP FOREIGN TABLE
- DROP FUNCTION
- DROP GROUP
- DROP INDEX
- DROP MATERIALIZED VIEW
- DROP OWNED
- DROP PUBLICATION
- DROP REDACTION POLICY
- DROP ROW LEVEL SECURITY POLICY
- DROP PROCEDURE
- DROP RESOURCE POOL
- DROP ROLE
- DROP SCHEMA
- DROP SEQUENCE
- DROP SERVER
- DROP SUBSCRIPTION
- DROP SYNONYM
- DROP TABLE
- DROP TEXT SEARCH CONFIGURATION
- DROP TEXT SEARCH DICTIONARY
- DROP TRIGGER
- DROP TYPE
- DROP USER
- DROP VIEW
- FETCH
- MOVE
- REFRESH MATERIALIZED VIEW
- REINDEX
- RENAME TABLE
- RESET
- SET
- SET CONSTRAINTS
- SET ROLE
- SET SESSION AUTHORIZATION
- SHOW
- TRUNCATE
- VACUUM
- DML Syntax
- DCL Syntax
- DQL Syntax
- TCL Syntax
-
SQL Syntax Reference (8.1.3.x)
- GaussDB(DWS) SQL Overview
- Differences Between GaussDB(DWS) and PostgreSQL
- Keyword
-
Data Types
- Numeric Types
- Monetary Types
- Boolean Type
- Character Types
- Binary Data Types
- Date/Time Types
- Geometric Types
- Array
- Enumeration Type
- Network Address Types
- Bit String Types
- Text Search Types
- UUID Type
- JSON Types
- RoaringBitmap
- HLL Data Types
- Object Identifier Types
- Pseudo-Types
- Range Types
- Composite Types
- Data Types Supported by Column-Store Tables
- XML
- Constant and Macro
-
Functions and Operators
- Character Processing Functions and Operators
- Binary String Functions and Operators
- Bit String Functions and Operators
- Mathematical Functions and Operators
- Date and Time Processing Functions and Operators
- SEQUENCE Functions
- Array Functions and Operators
- Logical Operators
- Comparison Operators
- Pattern Matching Operators
- Aggregate Functions
- Window Functions
- Type Conversion Functions
- JSON/JSONB Functions and Operators
- Security Functions
- Conditional Expression Functions
- Range Functions and Operators
- Data Masking Functions
- Roaring Bitmap Functions and Operators
- UUID Functions
- Text Search Functions and Operators
- HLL Functions and Operators
- Set Returning Functions
- Geometric Functions and Operators
- Network Address Functions and Operators
- System Information Functions
- System Administration Functions
- Database Object Functions
- Residual File Management Functions
- Statistics Information Functions
- Trigger Functions
- XML Functions
- Call Stack Recording Functions
- Expressions
- Type Conversion
- Full Text Search
- System Operation
- Transaction Management
-
DDL Syntax
- DDL Syntax Overview
- ALTER DATABASE
- ALTER FOREIGN TABLE (GDS Import and Export)
- ALTER FOREIGN TABLE (for HDFS or OBS)
- ALTER FOREIGN TABLE (SQL on other GaussDB(DWS))
- ALTER FUNCTION
- ALTER GROUP
- ALTER INDEX
- ALTER LARGE OBJECT
- ALTER REDACTION POLICY
- ALTER RESOURCE POOL
- ALTER ROLE
- ALTER ROW LEVEL SECURITY POLICY
- ALTER SCHEMA
- ALTER SEQUENCE
- ALTER SERVER
- ALTER SESSION
- ALTER SYNONYM
- ALTER SYSTEM KILL SESSION
- ALTER TABLE
- ALTER TABLE PARTITION
- ALTER TEXT SEARCH CONFIGURATION
- ALTER TEXT SEARCH DICTIONARY
- ALTER TRIGGER
- ALTER TYPE
- ALTER USER
- ALTER VIEW
- CLEAN CONNECTION
- CLOSE
- CLUSTER
- COMMENT
- CREATE BARRIER
- CREATE DATABASE
- CREATE FOREIGN TABLE (for GDS Import and Export)
- CREATE FOREIGN TABLE (SQL on OBS or Hadoop)
- CREATE FOREIGN TABLE (for OBS Import and Export)
- CREATE FOREIGN TABLE (SQL on other GaussDB(DWS))
- CREATE FUNCTION
- CREATE GROUP
- CREATE INDEX
- CREATE REDACTION POLICY
- CREATE ROW LEVEL SECURITY POLICY
- CREATE PROCEDURE
- CREATE RESOURCE POOL
- CREATE ROLE
- CREATE SCHEMA
- CREATE SEQUENCE
- CREATE SERVER
- CREATE SYNONYM
- CREATE TABLE
- CREATE TABLE AS
- CREATE TABLE PARTITION
- CREATE TEXT SEARCH CONFIGURATION
- CREATE TEXT SEARCH DICTIONARY
- CREATE TRIGGER
- CREATE TYPE
- CREATE USER
- CREATE VIEW
- CURSOR
- DROP DATABASE
- DROP FOREIGN TABLE
- DROP FUNCTION
- DROP GROUP
- DROP INDEX
- DROP OWNED
- DROP REDACTION POLICY
- DROP ROW LEVEL SECURITY POLICY
- DROP PROCEDURE
- DROP RESOURCE POOL
- DROP ROLE
- DROP SCHEMA
- DROP SEQUENCE
- DROP SERVER
- DROP SYNONYM
- DROP TABLE
- DROP TEXT SEARCH CONFIGURATION
- DROP TEXT SEARCH DICTIONARY
- DROP TRIGGER
- DROP TYPE
- DROP USER
- DROP VIEW
- FETCH
- MOVE
- REINDEX
- RENAME TABLE
- RESET
- SET
- SET CONSTRAINTS
- SET ROLE
- SET SESSION AUTHORIZATION
- SHOW
- TRUNCATE
- VACUUM
- DML Syntax
- DCL Syntax
- DQL Syntax
- TCL Syntax
- Historical Versions
-
SQL Syntax Reference (9.1.0.x)
-
Performance Tuning
- Overview of Query Performance Optimization
- Query Execution Process
- SQL Execution Plan
-
SQL Optimization Guide
- Optimization Process
- Updating Statistics
- Reviewing and Modifying a Table Definition
- SQL Statement Rewriting Rules
- Typical SQL Optimization Methods
- Hint-based Tuning
- Routinely Maintaining Tables
- Routinely Recreating an Index
- Adjusting Key Parameters During SQL Tuning
- Configuring SMP
- Querying SQL Statements That Affect Performance Most
-
Optimization Cases
- Case: Selecting an Appropriate Distribution Column
- Case: Creating an Appropriate Index
- Case: Adding NOT NULL for JOIN Columns
- Case: Pushing Down Sort Operations to DNs
- Case: Configuring cost_param for Better Query Performance
- Case: Adjusting the Partial Clustering Key
- Case: Adjusting the Table Storage Mode in a Medium Table
- Case: Reconstructing Partition Tables
- Case: Adjusting the GUC Parameter best_agg_plan
- Case: Rewriting SQL Statements and Eliminating Prune Interference
- Case: Rewriting SQL Statements and Deleting in-clause
- Case: Setting Partial Cluster Keys
- Case: Converting from NOT IN to NOT EXISTS
- SQL Execution Troubleshooting
- query_band Load Identification
- Common Performance Parameter Optimization Design
-
Tool Guide
- Overview
- Downloading Related Tools
- gsql
-
Data Studio
- About Data Studio
- Downloading and Installing the Data Studio Client
- Configuring Data Studio
- Configuring SSL Connection
- Connection Management
- Database Management
-
SQL Terminal Management
- Opening Multiple SQL Terminal Tabs
- Managing the SQL Query Execution History
- Opening and Saving SQL Scripts
- Viewing Table Properties, PL/SQL Functions/Procedures on the SQL Terminal Page
- Terminating an Ongoing SQL Query
- Formatting of SQL Queries
- Selecting a DB Object in the SQL Terminal
- Viewing the Execution Plan and Costs
- Viewing the Query Execution Plan and Cost Graphically
- Working with SQL Terminals
- Exporting Query Results
- Managing SQL Terminal Connections
- Security Management
- Troubleshooting
- FAQs
- GDS
-
DSC
- About This Document
- Introduction to DSC
- Using DSC
-
Teradata Syntax Migration
- Supported Keywords and Features
- Constraints and Limitations
- Data Type
- Functions and Operators
- Migrating Tables
- Migrating Indexes
- Migrating Views
- COLLECT STATISTICS
- ACCESS LOCK
- DBC.COLUMNS
- DBC.TABLES
- DBC.INDICES
- SHOW STATS VALUES SEQUENCED
- COMMENT
- Data Manipulation Language (DML)
- Type Casting and Formatting
- BTEQ Utility Command
- Teradata Formats
- System Views
-
MySQL Syntax Migrating
- Supported Keywords and Features
- Data Types
- Functions and Expressions
-
Table (Optional Parameters and Operations)
- ALGORITHM
- ALTER TABLE RENAME
- AUTO_INCREMENT
- AVG_ROW_LENGTH
- BLOCK_SIZE
- CHARSET
- CHECKSUM
- CLUSTERED KEY
- COLLATE
- COMMENT
- CONNECTION
- DEFAULT
- DELAY_KEY_WRITE
- DISTRIBUTE BY
- DIRECTORY
- ENGINE
- FOREIGN_KEY_CHECKS
- IF NOT EXISTS
- INDEX_ALL
- INSERT_METHOD
- KEY_BLOCK_SIZE
- LOCK
- MAX_ROWS
- MIN_ROWS
- PACK_KEYS
- PARTITION BY
- PASSWORD
- ROW_FORMAT
- STATS_AUTO_RECALC
- STATS_PERSISTENT
- STATS_SAMPLE_PAGES
- UNION
- WITH AS
- CHANGE (Column Modification)
- CHECK Constraint
- DROP (Table Deletion)
- LIKE (Table Cloning)
- MODIFY (Modifying a Column)
- TRUNCATE (Table Deletion)
- ROUNDROBIN Table
- RENAME (Table Renaming)
- SET|DROP COLUMN DEFAULT VALUE
- Renaming a Column
- Row-Store/Column-Store Table Compression
- Adding/Deleting a Column
- Indexes
- Comment
- Databases
- Data Manipulation Language (DML)
- Transaction Management and Database Management
- SQL-Server Syntax Migration
-
Oracle Syntax Migration
- Schema Objects
- COMPRESS Phrase
- Bitmap Index
- Custom Tablespace
- Supplemental Log Data
- LONG RAW
- SYS_GUID
- DML
- Pseudo Columns
- OUTER JOIN
- OUTER QUERY (+)
- CONNECT BY
- System Functions
- PL/SQL
- PL/SQL Collections (Using User-Defined Types)
- PL/SQL Packages
- VARRAY
- Granting Execution Permissions
- Package Name List
- Data Type
- Netezza Syntax Migration
- FAQs
- Troubleshooting
- Glossary
- DataCheck
- DWS-Connector
- Server Tool
-
API Reference
- Before You Start
- API Overview
- Calling APIs
- Getting Started
-
API Description
- AZ
-
Cluster Management
- Creating a Cluster
- Creating a Cluster (V2)
- Creating a Logical Cluster
- Converting a Physical Cluster to a Logical Cluster
- Querying the Cluster List
- Querying the Logical Cluster List
- Querying Task Information About a Logical Cluster
- Querying Disk Information of a Logical Cluster
- Querying the Node List
- Querying Information About Available Ring Nodes in a Logical Cluster
- Querying Information About Ring Nodes in a Cluster Topology
- Querying Cluster Details
- Querying Node Types
- Deleting Clusters
- Deleting a Logical Cluster
- Editing a Logical Cluster
- Restarting a Logical Cluster
- Switching to a Logical Cluster
- Deleting a Node
- Scaling Out with Idle Nodes
- Resuming Redistribution
- Suspending Redistribution
- Restarting a Cluster
- Scaling Out a Cluster
- Resetting a Password
- Performing a Check Before Cluster Creation
- Scaling In a Cluster
- Delivering Redistribution
- Querying Redistribution Details
- Querying the DSS Storage Pool List
- Querying the Resource Statistics
- Performing Primary-Standby Restoration
- Removing the Read-only Status
- Adding Disk Capacity
- Modifying a Maintenance Window
- Querying Cluster CN Nodes
- Adding CN Nodes in Batches
- Deleting CN Nodes in Batches
- Querying a Cluster Parameter Group
- Querying Cluster Parameter Settings
- Modifying Parameter Settings of a Cluster
- Querying Snapshot Statistics
- Querying the Nodes to Be Removed for Scale-In
- Querying Parameter Modification Audit Records
- Saving Cluster Description
- Querying an Instance
-
Snapshot Management
- Creating a Snapshot
- Querying the Snapshot List
- Querying a Snapshot Policy
- Querying Snapshot Details
- Deleting a Manual Snapshot
- Deleting a Snapshot Policy
- Restoring a Cluster
- Checking the Name of the Table to Be Restored
- Restoring a Table
- Obtaining Available Regions of a Cross-Region Snapshot
- Configuring Cross-Region Backup
- Querying All Cross-Region Snapshot Configurations
- Deleting Cross-Region Backup Configurations
- Copying a Snapshot
- Querying the Cluster Snapshot List
- Adding a Snapshot Policy
- Event Management
- Data Source
- Audit logs
-
Resource Management
- Setting the Resource Management Switch
- Querying the Resource Management Status
- Querying Resource Statistics
- Creating a Resource Pool
- Deleting a Resource Pool
- Querying the Resource Pool List
- Obtaining Resource Pool Details
- Updating Configuration Information of a Resource Pool
- Associating a Resource Pool with a User
- Obtaining the List of Users Bound to a Resource Pool
- Unbinding a User from a Resource Pool
- Creating a Resource Management Plan
- Querying the Resource Management Plan List
- Starting a Resource Management Plan
- Viewing Plan Execution Logs
- Querying Details About a Resource Management Plan
- Stopping a Resource Management Plan
- Deleting a Resource Management Plan
- Adding a Resource Management Plan Stage
- Querying Details About a Resource Management Plan Stage
- Deleting a Resource Management Plan Stage
- Switch to Another Resource Management Plan Stage
- Querying Cluster Schema Space Information
- Updating the Space Limit of a Schema
- Alarm Management
- Connection Management
- Tag Management
- Quota Management
-
DR Management
- Creating a DR Task
- Enabling DR
- Querying the DR List
- Querying DR Details
- Querying DR Progress
- Querying the List of Available DR Clusters
- Updating DR Configurations
- Switching to the DR Cluster
- Switching to the DR Cluster Upon Production Cluster Exceptions
- Performing Cluster Restoration
- Disabling DR
- Checking the DR Name
- Deleting a DR Task
- Job Management
-
Host Monitoring
- Querying the Host Overview
- Querying Disk Information
- Obtaining the NIC Status
- Querying Performance Monitoring Metrics
- Querying Historical Monitoring Data
- Querying Table Skew or Dirty Page Rate Information
- Querying the SQL List
- Querying SQL Execution Information
- Querying the List of Metrics Used by a Cluster
- Obtains the collected data of a specified metric.
- Managing Database Permissions
- Log Management
- Upgrade Management
- Application Cases
- Introduction
- Appendix
- SDK Reference
-
FAQs
- Top FAQs
-
Product Consulting
- Why Should I Use GaussDB(DWS)?
- Should I Choose Public Cloud GaussDB(DWS) or RDS?
- What Are the Differences Between GaussDB(DWS) Users and Roles?
- How Do I Check the Creation Time of a GaussDB(DWS) Database User?
- Learn How to Select a GaussDB(DWS) Region and AZ
- Is Data Secure in GaussDB(DWS)?
- Can I Modify the Security Group of a GaussDB(DWS) Cluster?
- What Is a Database/Data Warehouse/Data Lake/Lakehouse?
- How Are Dirty Pages Generated in GaussDB(DWS)?
- How Do I Use VPC Sharing to Process GaussDB(DWS) Resources?
-
Database Connections
- How Applications Communicate with GaussDB(DWS)?
- Does GaussDB(DWS) Support Third-Party Clients and JDBC and ODBC Drivers?
- What Should I Do If I Cannot Connect to a GaussDB(DWS) Cluster?
- Why Was I Not Notified of Failure Unbinding the EIP When GaussDB(DWS) Is Connected Over the Internet?
- How Do I Configure a Whitelist to Protect GaussDB(DWS) Clusters Available Through a Public IP Address?
-
Data Migration
- What Are the Differences Between Data Formats Supported by OBS and GDS Foreign Tables in GaussDB(DWS)?
- How Does GaussDB(DWS) Store Data?
- How Much Service Data Can Be Stored in GaussDB(DWS)?
- How to Import and Export Data in GaussDB(DWS) Using \copy?
- How Do I Implement Fault Tolerance Import Between Different GaussDB(DWS) Encoding Libraries
- Which Are the Factors That Affect GaussDB(DWS) Import Performance?
-
Database Usage
- How Do I Adjust GaussDB(DWS) Distribution Columns?
- How Do I View and Set the Character Set Encoding Format of the GaussDB(DWS) Database?
- What Do I Do If Date Type Is Automatically Converted to the Timestamp Type During GaussDB(DWS) Table Creation?
- Do I Need to Run VACUUM FULL and ANALYZE on Common Tables Periodically in GaussDB(DWS)?
- How Do I Export the Structure of a GaussDB(DWS) Table?
- How Do I Delete Table Data Efficiently in GaussDB(DWS)?
- How Do I View GaussDB(DWS) Foreign Table Information?
- How Will Data Be Stored in a GaussDB(DWS) Table If No Distribution Column Is Specified During Its Creation?
- How Do I Replace the Null Results with 0 in a GaussDB(DWS) Join Query?
- How Do I Check Whether a GaussDB(DWS) Table Is Row-Stored or Column-Stored?
- How Do I Query the Information About GaussDB(DWS) Column-Store Tables?
- Why Sometimes the GaussDB(DWS) Query Indexes Become Invalid?
- How Do I Use a User-Defined GaussDB(DWS) Function to Rewrite the CRC32() Function?
- What Is a GaussDB(DWS) Schema Starting with pg_toast_temp* or pg_temp*?
- Solutions to Inconsistent GaussDB(DWS) Query Results
- Which System Catalogs in GaussDB(DWS) Cannot Be Subjected to the VACUUM FULL Operation?
- In Which Scenarios Would a GaussDB(DWS) Statement Be "idle in transaction"?
- How Does GaussDB(DWS) Implement Row-to-Column and Column-to-Row Conversion?
- What Are the Differences Between Unique Constraints and Unique Indexes in GaussDB(DWS)?
- What Are the Differences Between GaussDB(DWS) Functions and Stored Procedures?
- How Do I Delete Duplicate Table Data in GaussDB(DWS)?
-
Cluster Management
- How Can I Clear and Reclaim the Storage Space in GaussDB(DWS)?
- Why Did the Used Storage in GaussDB(DWS) Shrink After Scale-out?
- How Is the Disk Space or Capacity of GaussDB(DWS) Calculated?
- How Can I Set the Session Threshold for Cloud Eye When Adding an Alarm Rule on GaussDB(DWS)?
- How Do I Determine Whether a GaussDB(DWS) Cluster Uses the x86 or Arm Architecture?
- What Should I Do If the GaussDB(DWS) Scale-out Check Fails?
- When Should I Add CNs or Scale Out a Cluster in GaussDB(DWS)?
- When to Modify GaussDB(DWS) Classic and Elastic Specifications and When to Perform Scale-Out and Scale-In?
- How Do I Select Between Small-Scale Multi-Node and Large-Scale Three-Node Clusters with Equivalent CPU and Memory in GaussDB(DWS)?
- What Are the Differences Between Cloud SSDs and Local SSDs in GaussDB(DWS)?
- What Are the Differences Between Hot Data Storage and Cold Data Storage in GaussDB(DWS)?
- What Should I Do If the Scale-In Button of GaussDB(DWS) Is Unavailable?
-
Account Permissions
- How Does GaussDB(DWS) Implement Workload Isolation?
- How Do I Change the Password of a GaussDB(DWS) Database Account When the Password Expires?
- How Do I Grant Table Permissions to a Specified GaussDB(DWS) User?
- How Do I Grant the Permission of a Schema to a Specified GaussDB(DWS) User?
- How Do I Create a GaussDB(DWS) Database Read-Only User?
- How Do I Create Private Users and Tables in a GaussDB(DWS) Database?
- How Do I Revoke the CONNECT ON DATABASE Permission of a User on GaussDB(DWS)?
- How Do I View the Table Permissions of a GaussDB(DWS) User?
- What Is the Ruby User in the GaussDB(DWS) Database?
-
Database Performance
- Why Is SQL Execution Slow After Long GaussDB(DWS) Usage?
- Why Does GaussDB(DWS) Perform Worse Than a Single-Server Database in Extreme Scenarios?
- How Do I View SQL Execution Records of a Certain Period When GaussDB(DWS) Service Read and Write Are Blocked?
- What is Operator Spilling in GaussDB(DWS)?
- GaussDB(DWS) CPU Resource Management
- Why Is the Execution of Common GaussDB(DWS) User Slower Than That of User dbadmin?
- What Are the Factors Related to the Single-Table Query Performance in GaussDB(DWS)?
- Backup and Restoration
-
Troubleshooting
-
Database Connections
- What Do I Do If gsql: command not found Is Displayed When I Run gsql to Connect to the Database?
- Database Cannot Be Connected Using the gsql Client
- An Error Indicating Too Many Client Connections Is Reported When a User Connects to a GaussDB(DWS) Database
- Cluster IP Address Cannot Be Pinged/Accessed
- Error "An I/O error occurred while sending to the backend" Is Reported During Service Execution
- JDBC/ODBC
-
Data Import and Export
- "ERROR: invalid byte sequence for encoding 'UTF8': 0x00" Is Reported When Data Is Imported to GaussDB(DWS) Using COPY FROM
- Data Import and Export Faults with GDS
- Failed to Create a GDS Foreign Table and An Error Is Reported Indicating that ROUNDROBIN Is Not Supported
- When CDM Is Used to Import MySQL Data to GaussDB(DWS), the Column Length Exceeds the Threshold and Data Synchronization Fails
- "Access Denied" Is Displayed When the SQL Statement for Creating an OBS Foreign Table Is Executed
- Disk Usage Increases After Data Fails to Be Imported Using GDS
- Error Message "out of memory" Is Displayed When GDS Is Used to Import Data
- Error Message "connection failure error" Is Displayed During GDS Data Transmission
- Data to Be Imported Contains Chinese When the DataArts Studio Service Is Used to Create a GaussDB(DWS) Foreign Table
- Database Parameter Modification
-
Account/Permission/Password
- How Do I Unlock an Account?
- Account Still Locked After Password Resetting
- After the Permission for Querying Tables in a Schema Is Granted to a User, the User Still Cannot Query the Tables
- How Do I Revoke the Permission of a User If grant select on table t1 to public Has Been Executed on a Table
- An Error Message Is Displayed When a Common User Executes the Statement for Creating or Deleting a GDS or OBS Foreign Table, Indicating that the User Does Not Have the Permission or the Permission Is Insufficient
- After the all Permission Is Granted to the Schema of a User, the Error Message "ERROR: current user does not have privilege to role tom" Persists During Table Creation
- An Error Message Is Reported During Statement Execution, Indicating that the User Does Not Have the Required Permission
- A User Cannot Be Deleted Due to Its Dependencies
-
Cluster Performance
- Lock Wait Detection
- During SQL Execution, a Table Deadlock Occurs and An Error Stating LOCK_WAIT_TIMEOUT Is Reported
- Error "abort transaction due to concurrent update" Is Reported During SQL Execution
- Solution to High Disk Usage and Cluster Read-Only
- SQL Execution Is Slow with Low Performance and Sometimes Does Not End After a Long Period of Time
- Data Skew Causes Slow SQL Statement Execution and Operations Fail on Large Tables
- Table Size Does not Change After VACUUM FULL Is Executed on the Table
- VACUUM Is Executed After Table Data Deletion, But the Space Is Not Released
- Error "lock wait timeout" Is Reported When VACUUM FULL Is Executed
- VACUUM FULL Is Slow
- Table Bloating Causes Slow SQL Query and Failed Data Loading on the GUI
- Memory Overflow Occurs in a Cluster
- Statements with User-defined Functions Cannot Be Pushed Down
- Column-Store Tables Cannot Be Updated or Table Bloat Occurs
- Table Bloat Occurs After Data Is Inserted into a Column-Store Table for Multiple Times
- Writing Data to GaussDB(DWS) Is Slow and Client Data Is Stacked
- Low Query Efficiency
- Poor Query Performance Due to the Lack of Statistics
- Execution of SQL Statements Is Slow Due to Nested Loops in Execution Plans
- SQL Query Is Slow Because Partitions Are Not Pruned
- Optimizer Uses Nested Loop Due to the Small Estimated Number of Rows and the Performance Deteriorates
- SQL Statements Contain the in Constant and No Result Is Returned After SQL Statement Execution
- Performance of Single-Table Point Query Is Poor
- CCN Queuing Under Dynamic Load Management
- Performance Deterioration Due to Data Bloat
- Slow Performance Caused by Too Many Small CUs in Column Storage
- Reducing I/O Usage
- Tuning Systems with High CPU Usage
- Reducing Memory Usage
- Cluster Exceptions
-
Database Use
- An Error Is Reported When Data Is Inserted or Updated, Indicating that the Distribution Key Cannot Be Updated
- "Connection reset by peer" Is Displayed When a User Executes an SQL Statement
- "value too long for type character varying" Is Displayed When VARCHAR(n) Stores Chinese Characters
- Case Sensitivity in SQL Statements
- cannot drop table test because other objects depend on it Is Displayed When a Table Is Deleted
- Failed to Execute MERGE INTO UPDATE for Multiple Tables
- JDBC Error Occurs Due to session_timeout Settings
- DROP TABLE Fails to Be Executed
- Execution Results of the string_agg Function Are Inconsistent
- Error "could not open relation with OID xxxx" Is Reported During Table Size Query
- DROP TABLE IF EXISTS Syntax Misuse
- Different Data Is Displayed for the Same Table Queried By Multiple Users
- When a User Specifies Only an Index Name to Modify the Index, A Message Indicating That the Index Does Not Exist Is Displayed
- An Error Is Displayed Indicating Schema Already Exists When Executing CREATE SCHEMA Statement
- Failed to Delete a Database and an Error Is Reported Indicating that a Session Is Connected to the Database
- Byte Type Is Returned After a Table Column of the Character Type Is Read in Java
- "ERROR:start value of partition 'XX' NOT EQUAL up-boundary of last partition." Is Displayed When Operations Related to Table Partitions Are Performed
- Reindexing Fails
- A View Failed to Be Queried
- Global SQL Query
- How Do I Determine Whether UPDATE or DELETE Has Been Executed on a Table?
- "Can't fit xid into page" Is Reported
- "unable to get a stable set of rows in the source table" Is Reported
- DWS Metadata Inconsistency - Abnormal Partition Index
- An Error Is Reported When the TRUNCATE Command Is Executed on the System Table gs_wlm_session_info
- "inserted partition key does not map to any table partition" Is Reported When Data Is Inserted into a Partitioned Table
- Error upper boundary of adding partition MUST overtop last existing partition Is Reported When a New Partition Is Added to a Range Partitioned Table
- Error Reported During Table Query: "missing chunk number %d for toast value %u in pg_toast_XXXX"
- When Inserting Data Into a Table, An Error Is Reported: "duplicate key value violates unique constraint "%s""
- Error could not determine which collation to use for string hashing Reported During Service Execution
- When the ODBC Driver of GaussDB(DWS) Is Used, Content of Fields of the Character Type in the SQL Query Result Is Truncated
- Execution Plan Scan Hints Do Not Take Effect
- Error "invalid input syntax for xxx" Is Reported During Data Type Conversion
- Error UNION types %s and %s cannot be matched Is Reported
- "ERROR: Non-deterministic UPDATE" Is Reported During Update
- Error Reported During Data Insertion: null value in column ' %s' violates not-null constraint
- Error "unable to get a stable set of rows in the source table"
- Query Results Are Inconsistent in Oracle, Teradata, and MySQL Compatibility Modes
-
Database Connections
- Videos
- Performance White Paper
-
Technical White Paper
- GaussDB(DWS)
- Platforms and Technical Specifications Supported by GaussDB(DWS)
-
GaussDB(DWS) Core Technologies
- Shared-Nothing Architecture
- Data Distribution in a Distributed System
- Fully Parallel Query
- Vectorized Executor and Hybrid Row-Column Storage Engine
- Resource Monitoring and Management
- Distributed Transactions
- Online Scale-Out
- SQL on Anywhere
- Cluster Management and HA
- SQL Self-Diagnosis
- Transparent Data Encryption
- Data Masking
- Data Backup and Disaster Recovery
- GaussDB(DWS) Tools
- External APIs
-
Error Code Reference
-
8.2.0 and earlier versions
- Management Console Error Code
-
Data Warehouse Service Error Codes
- Description of SQL Error Codes
- Third-Party Library Error Codes
- GAUSS-00001 -- GAUSS-00100
- GAUSS-00101 -- GAUSS-00200
- GAUSS-00201 -- GAUSS-00300
- GAUSS-00301 -- GAUSS-00400
- GAUSS-00401 -- GAUSS-00500
- GAUSS-00501 -- GAUSS-00600
- GAUSS-00601 -- GAUSS-00700
- GAUSS-00701 -- GAUSS-00800
- GAUSS-00801 -- GAUSS-00900
- GAUSS-00901 -- GAUSS-01000
- GAUSS-01001 -- GAUSS-01100
- GAUSS-01101 -- GAUSS-01200
- GAUSS-01201 -- GAUSS-01300
- GAUSS-01301 -- GAUSS-01400
- GAUSS-01401 -- GAUSS-01500
- GAUSS-01501 -- GAUSS-01600
- GAUSS-01601 -- GAUSS-01700
- GAUSS-01701 -- GAUSS-01800
- GAUSS-01801 -- GAUSS-01900
- GAUSS-01901 -- GAUSS-02000
- GAUSS-02001 -- GAUSS-02100
- GAUSS-02101 -- GAUSS-02200
- GAUSS-02201 -- GAUSS-02300
- GAUSS-02301 -- GAUSS-02400
- GAUSS-02401 -- GAUSS-02500
- GAUSS-02501 -- GAUSS-02600
- GAUSS-02601 -- GAUSS-02700
- GAUSS-02701 -- GAUSS-02800
- GAUSS-02801 -- GAUSS-02900
- GAUSS-02901 -- GAUSS-03000
- GAUSS-03001 -- GAUSS-03100
- GAUSS-03101 -- GAUSS-03200
- GAUSS-03201 -- GAUSS-03300
- GAUSS-03301 -- GAUSS-03400
- GAUSS-03401 -- GAUSS-03500
- GAUSS-03501 -- GAUSS-03600
- GAUSS-03601 -- GAUSS-03700
- GAUSS-03701 -- GAUSS-03800
- GAUSS-03801 -- GAUSS-03900
- GAUSS-03901 -- GAUSS-04000
- GAUSS-04001 -- GAUSS-04100
- GAUSS-04101 -- GAUSS-04200
- GAUSS-04201 -- GAUSS-04300
- GAUSS-04301 -- GAUSS-04400
- GAUSS-04401 -- GAUSS-04500
- GAUSS-04501 -- GAUSS-04600
- GAUSS-04601 -- GAUSS-04700
- GAUSS-04701 -- GAUSS-04800
- GAUSS-04901 -- GAUSS-04999
- GAUSS-05101 -- GAUSS-05200
- GAUSS-05201 -- GAUSS-05800
- GAUSS-05801 -- GAUSS-05900
- GAUSS-05901 -- GAUSS-05999
- GAUSS-06101 -- GAUSS-06200
- GAUSS-50000 -- GAUSS-50999
- GAUSS-51000 -- GAUSS-51999
- GAUSS-52000 -- GAUSS-52999
- GAUSS-53000 -- GAUSS-53999
- OE000
- 8.2.1 or later versions
-
8.2.0 and earlier versions
- Glossary
-
More Documents
-
User Guide
- Service Overview
- Getting Started
- Process for Using GaussDB(DWS)
- Preparations
- Cluster Configuration
-
Cluster Connection
- Methods of Connecting to a Cluster
- Obtaining the Cluster Connection Address
- Using the gsql CLI Client to Connect to a Cluster
- Using the Data Studio GUI Client to Connect to a Cluster
- Using the JDBC and ODBC Drivers to Connect to a Cluster
- Using the Python Library psycopg2 to Connect to a Cluster
- Using the Python Library PyGreSQL to Connect to a Cluster
- Managing Database Connections
-
Clusters
- Checking the Cluster Status
- Viewing Basic Cluster Information
- Managing Access Domain Names
- Cluster Scale-out
- Performing a Primary/Standby Switchback
- Cluster Upgrade
- Password Reset
- Cluster Restart
- Modifying Database Parameters
- MRS Data Sources
- Managing Logical Clusters
- Managing Tags
- Deleting Clusters
- Managing Parameter Templates
- Managing Clusters That Fail to Be Created
- Cluster HA
- Monitoring and Alarms
- Cluster Security Management
- Audit Logs
-
FAQs
-
General Problems
- Why Are Data Warehouses Necessary?
- What Are the Differences Between a Data Warehouse and the Hadoop Big Data Platform?
- Why Should I Use GaussDB(DWS)?
- When Should I Use GaussDB(DWS) and MRS?
- What Are the Differences Between GaussDB(DWS) and Hive in Functions?
- What Is the User Quota?
- What Are the Differences Between Users and Roles?
- How Do I Check the Creation Time of a Database User?
- Regions and AZs
- Is My Data Secure in GaussDB(DWS)?
- How Is GaussDB(DWS) Secured?
- Can I Modify the Security Group of a GaussDB(DWS) Cluster?
- What Is a Database/Data Warehouse/Data Lake/Lakehouse?
-
Cluster Management
- What Do I Do If Creating a GaussDB(DWS) Cluster Failed?
- How Can I Clear and Reclaim the Storage Space?
- Why Did the Used Storage Shrink After Scale-out?
- How Do I View Node Metrics (CPU, Memory, and Disk Usage)?
- Does GaussDB(DWS) Support a Single Node for a Learning Environment?
- How Is the Disk Space or Capacity of GaussDB(DWS) Calculated?
- What Are the gaussdb and postgres Databases of GaussDB(DWS)?
- How Do I Set the Maximum Number of Sessions When Adding an Alarm Rule on Cloud Eye?
- When Should I Add CNs or Scale out a cluster?
- What Are the Differences Between Hot Data Storage and Cold Data Storage?
-
Database Connections
- How Applications Communicate with GaussDB(DWS)?
- Does GaussDB(DWS) Support Third-Party Clients and JDBC and ODBC Drivers?
- Can I Connect to GaussDB(DWS) Cluster Nodes Using SSH?
- What Should I Do If I Cannot Connect to a Data Warehouse Cluster?
- Why Was I Not Notified of Failure Unbinding the EIP When GaussDB(DWS) Is Connected Over the Internet?
- How Do I Configure a Whitelist to Protect Clusters Available Through a Public IP Address?
-
Data Import and Export
- What Are the Differences Between Data Formats Supported by OBS and GDS Foreign Tables?
- How Do I Import Incremental Data Using an OBS Foreign Table?
- How Can I Import Data to GaussDB(DWS)?
- How Much Service Data Can a Data Warehouse Store?
- How Do I Use \Copy to Import and Export Data?
- Can I Export GaussDB(DWS) Data from/to OBS Across Regions?
- How Do I Import GaussDB(DWS)/Oracle/MySQL/SQL Server Data to GaussDB(DWS) (Whole Database Migration)?
- Can I Import Data over the Public/External Network Using GDS?
- Which Are the Factors That Affect GaussDB(DWS) Import Performance?
-
Account, Password, and Permissions
- How Does GaussDB(DWS) Implement Workload Isolation?
- How Do I Change the Password of a Database Account When the Password Expires?
- How Do I Grant Table Permissions to a User?
- How Do I Grant Schema Permissions to a User?
- How Do I Create a Database Read-only User?
- How Do I Create Private Database Users and Tables?
- How Do I Revoke the CONNECT ON DATABASE Permission from a User?
- How Do I View the Table Permissions of a User?
- Who Is User Ruby?
-
Database Usage
- How Do I Change Distribution Columns?
- How Do I View and Set the Database Character Encoding?
- What Do I Do If Date Type Is Automatically Converted to the Timestamp Type During Table Creation?
- Do I Need to Run VACUUM FULL and ANALYZE on Common Tables Periodically?
- Do I Need to Set a Distribution Key After Setting a Primary Key?
- Is GaussDB(DWS) Compatible with PostgreSQL Stored Procedures?
- What Are Partitioned Tables, Partitions, and Partition Keys?
- How Can I Export the Table Structure?
- How Can I Export All Tables and Views from a Database?
- How Can I Delete Table Data Efficiently?
- How Do I View Foreign Table Information?
- If No Distribution Column Is Specified, How Will Data Be Stored?
- How Do I Replace the Null Result with 0?
- How Do I Check Whether a Table Is Row-Stored or Column-Stored?
- How Do I Query the Information About GaussDB(DWS) Column-Store Tables?
- Why Sometimes the GaussDB(DWS) Query Indexes Become Invalid?
- How Do I Use a User-Defined Function to Rewrite the CRC32() Function?
- What Are the Schemas Starting with pg_toast_temp* or pg_temp*?
- Solutions to Inconsistent GaussDB(DWS) Query Results
- Which System Catalogs That the VACUUM FULL Operation Cannot Be Performed on?
- In Which Scenarios Would a Statement Be "idle in transaction"?
- Database Performance
- Snapshot Backup and Restoration
-
General Problems
- Change History
- API Reference (ME-Abu Dhabi Region)
-
Developer Guide (ME-Abu Dhabi Region)
- Welcome
- System Overview
-
Data Migration
- Data Migration to GaussDB(DWS)
- Data Import
- Full Database Migration
- Meta-command Migration
- Data Export
- Appendices
- Syntax Compatibility Differences Among Oracle, Teradata, and MySQL
- Database Security Management
- Development and Design Proposal
-
Guide: JDBC- or ODBC-Based Development
- Development Specifications
- Downloading Drivers
-
JDBC-Based Development
- JDBC Package and Driver Class
- Development Process
- Loading a Driver
- Connecting to a Database
- Executing SQL Statements
- Processing Data in a Result Set
- Closing the Connection
- Example: Common Operations
- Example: Retrying SQL Queries for Applications
- Example: Importing and Exporting Data Through Local Files
- Example: Migrating Data from MySQL to GaussDB(DWS)
-
JDBC Interface Reference
- java.sql.Connection
- java.sql.CallableStatement
- java.sql.DatabaseMetaData
- java.sql.Driver
- java.sql.PreparedStatement
- java.sql.ResultSet
- java.sql.ResultSetMetaData
- java.sql.Statement
- javax.sql.ConnectionPoolDataSource
- javax.sql.DataSource
- javax.sql.PooledConnection
- javax.naming.Context
- javax.naming.spi.InitialContextFactory
- CopyManager
- ODBC-Based Development
- PostGIS Extension
- Resource Load Management
-
Query Performance Optimization
- Optimization Overview
- Overview of Query Performance Optimization
- Query Analysis
- System Optimization
-
Query Improvement
- Query Execution Process
- Introduction to the SQL Execution Plan
- Optimization Process
- Updating Statistics
- Reviewing and Modifying a Table Definition
- Typical SQL Optimization Methods
- Experience in Rewriting SQL Statements
- Adjusting Key Parameters During SQL Tuning
- Hint-based Tuning
- Routinely Maintaining Tables
- Routinely Recreating an Index
- Configuring the SMP
-
Optimization Cases
- Case: Selecting an Appropriate Distribution Column
- Case: Creating an Appropriate Index
- Case: Adding NOT NULL for JOIN Columns
- Case: Pushing Down Sort Operations to DNs
- Case: Configuring cost_param for Better Query Performance
- Case: Adjusting the Distribution Key
- Case: Adjusting the Partial Clustering Key
- Case: Adjusting the Table Storage Mode in a Medium Table
- Case: Adjusting the Local Clustering Column
- Case: Reconstructing Partition Tables
- Case: Adjusting the GUC Parameter best_agg_plan
- Case: Rewriting SQL and Deleting Subqueries (Case 1)
- Case: Rewriting SQL and Deleting Subqueries (Case 2)
- Case: Rewriting SQL Statements and Eliminating Prune Interference
- Case: Rewriting SQL Statements and Deleting in-clause
- Case: Setting Partial Cluster Keys
- SQL Execution Troubleshooting
- Common Performance Parameter Optimization Design
- User-Defined Functions
- Stored Procedures
-
System Catalogs and System Views
- Overview of System Catalogs and System Views
-
System Catalogs
- GS_OBSSCANINFO
- GS_WLM_INSTANCE_HISTORY
- GS_WLM_OPERATOR_INFO
- GS_WLM_SESSION_INFO
- GS_WLM_USER_RESOURCE_HISTORY
- PG_AGGREGATE
- PG_AM
- PG_AMOP
- PG_AMPROC
- PG_ATTRDEF
- PG_ATTRIBUTE
- PG_AUTHID
- PG_AUTH_HISTORY
- PG_AUTH_MEMBERS
- PG_CAST
- PG_CLASS
- PG_COLLATION
- PG_CONSTRAINT
- PG_CONVERSION
- PG_DATABASE
- PG_DB_ROLE_SETTING
- PG_DEFAULT_ACL
- PG_DEPEND
- PG_DESCRIPTION
- PG_ENUM
- PG_EXTENSION
- PG_EXTENSION_DATA_SOURCE
- PG_FOREIGN_DATA_WRAPPER
- PG_FOREIGN_SERVER
- PG_FOREIGN_TABLE
- PG_INDEX
- PG_INHERITS
- PG_JOBS
- PG_LANGUAGE
- PG_LARGEOBJECT
- PG_LARGEOBJECT_METADATA
- PG_NAMESPACE
- PG_OBJECT
- PG_OBSSCANINFO
- PG_OPCLASS
- PG_OPERATOR
- PG_OPFAMILY
- PG_PARTITION
- PG_PLTEMPLATE
- PG_PROC
- PG_RANGE
- PG_REDACTION_COLUMN
- PG_REDACTION_POLICY
- PG_RLSPOLICY
- PG_RESOURCE_POOL
- PG_REWRITE
- PG_SECLABEL
- PG_SHDEPEND
- PG_SHDESCRIPTION
- PG_SHSECLABEL
- PG_STATISTIC
- PG_STATISTIC_EXT
- PG_SYNONYM
- PG_TABLESPACE
- PG_TRIGGER
- PG_TS_CONFIG
- PG_TS_CONFIG_MAP
- PG_TS_DICT
- PG_TS_PARSER
- PG_TS_TEMPLATE
- PG_TYPE
- PG_USER_MAPPING
- PG_USER_STATUS
- PG_WORKLOAD_ACTION
- PGXC_CLASS
- PGXC_GROUP
- PGXC_NODE
-
System Views
- ALL_ALL_TABLES
- ALL_CONSTRAINTS
- ALL_CONS_COLUMNS
- ALL_COL_COMMENTS
- ALL_DEPENDENCIES
- ALL_IND_COLUMNS
- ALL_IND_EXPRESSIONS
- ALL_INDEXES
- ALL_OBJECTS
- ALL_PROCEDURES
- ALL_SEQUENCES
- ALL_SOURCE
- ALL_SYNONYMS
- ALL_TAB_COLUMNS
- ALL_TAB_COMMENTS
- ALL_TABLES
- ALL_USERS
- ALL_VIEWS
- DBA_DATA_FILES
- DBA_USERS
- DBA_COL_COMMENTS
- DBA_CONSTRAINTS
- DBA_CONS_COLUMNS
- DBA_IND_COLUMNS
- DBA_IND_EXPRESSIONS
- DBA_IND_PARTITIONS
- DBA_INDEXES
- DBA_OBJECTS
- DBA_PART_INDEXES
- DBA_PART_TABLES
- DBA_PROCEDURES
- DBA_SEQUENCES
- DBA_SOURCE
- DBA_SYNONYMS
- DBA_TAB_COLUMNS
- DBA_TAB_COMMENTS
- DBA_TAB_PARTITIONS
- DBA_TABLES
- DBA_TABLESPACES
- DBA_TRIGGERS
- DBA_VIEWS
- DUAL
- GLOBAL_REDO_STAT
- GLOBAL_REL_IOSTAT
- GLOBAL_STAT_DATABASE
- GLOBAL_WORKLOAD_SQL_COUNT
- GLOBAL_WORKLOAD_SQL_ELAPSE_TIME
- GLOBAL_WORKLOAD_TRANSACTION
- GS_ALL_CONTROL_GROUP_INFO
- GS_CLUSTER_RESOURCE_INFO
- GS_INSTR_UNIQUE_SQL
- GS_REL_IOSTAT
- GS_NODE_STAT_RESET_TIME
- GS_SESSION_CPU_STATISTICS
- GS_SESSION_MEMORY_STATISTICS
- GS_SQL_COUNT
- GS_WAIT_EVENTS
- GS_WLM_OPERAROR_INFO
- GS_WLM_OPERATOR_HISTORY
- GS_WLM_OPERATOR_STATISTICS
- GS_WLM_SESSION_INFO
- GS_WLM_SESSION_HISTORY
- GS_WLM_SESSION_STATISTICS
- GS_WLM_SQL_ALLOW
- GS_WORKLOAD_SQL_COUNT
- GS_WORKLOAD_SQL_ELAPSE_TIME
- GS_WORKLOAD_TRANSACTION
- GS_STAT_DB_CU
- GS_STAT_SESSION_CU
- GS_TOTAL_NODEGROUP_MEMORY_DETAIL
- GS_USER_TRANSACTION
- GS_VIEW_DEPENDENCY
- GS_VIEW_DEPENDENCY_PATH
- GS_VIEW_INVALID
- PG_AVAILABLE_EXTENSION_VERSIONS
- PG_AVAILABLE_EXTENSIONS
- PG_BULKLOAD_STATISTICS
- PG_COMM_CLIENT_INFO
- PG_COMM_DELAY
- PG_COMM_STATUS
- PG_COMM_RECV_STREAM
- PG_COMM_SEND_STREAM
- PG_CONTROL_GROUP_CONFIG
- PG_CURSORS
- PG_EXT_STATS
- PG_GET_INVALID_BACKENDS
- PG_GET_SENDERS_CATCHUP_TIME
- PG_GROUP
- PG_INDEXES
- PG_JOB
- PG_JOB_PROC
- PG_JOB_SINGLE
- PG_LIFECYCLE_DATA_DISTRIBUTE
- PG_LOCKS
- PG_NODE_ENV
- PG_OS_THREADS
- PG_POOLER_STATUS
- PG_PREPARED_STATEMENTS
- PG_PREPARED_XACTS
- PG_QUERYBAND_ACTION
- PG_REPLICATION_SLOTS
- PG_ROLES
- PG_RULES
- PG_RUNNING_XACTS
- PG_SECLABELS
- PG_SESSION_WLMSTAT
- PG_SESSION_IOSTAT
- PG_SETTINGS
- PG_SHADOW
- PG_SHARED_MEMORY_DETAIL
- PG_STATS
- PG_STAT_ACTIVITY
- PG_STAT_ALL_INDEXES
- PG_STAT_ALL_TABLES
- PG_STAT_BAD_BLOCK
- PG_STAT_BGWRITER
- PG_STAT_DATABASE
- PG_STAT_DATABASE_CONFLICTS
- PG_STAT_GET_MEM_MBYTES_RESERVED
- PG_STAT_USER_FUNCTIONS
- PG_STAT_USER_INDEXES
- PG_STAT_USER_TABLES
- PG_STAT_REPLICATION
- PG_STAT_SYS_INDEXES
- PG_STAT_SYS_TABLES
- PG_STAT_XACT_ALL_TABLES
- PG_STAT_XACT_SYS_TABLES
- PG_STAT_XACT_USER_FUNCTIONS
- PG_STAT_XACT_USER_TABLES
- PG_STATIO_ALL_INDEXES
- PG_STATIO_ALL_SEQUENCES
- PG_STATIO_ALL_TABLES
- PG_STATIO_SYS_INDEXES
- PG_STATIO_SYS_SEQUENCES
- PG_STATIO_SYS_TABLES
- PG_STATIO_USER_INDEXES
- PG_STATIO_USER_SEQUENCES
- PG_STATIO_USER_TABLES
- PG_THREAD_WAIT_STATUS
- PG_TABLES
- PG_TIMEZONE_ABBREVS
- PG_TIMEZONE_NAMES
- PG_TOTAL_MEMORY_DETAIL
- PG_TOTAL_SCHEMA_INFO
- PG_TOTAL_USER_RESOURCE_INFO
- PG_USER
- PG_USER_MAPPINGS
- PG_VIEWS
- PG_WLM_STATISTICS
- PGXC_BULKLOAD_PROGRESS
- PGXC_BULKLOAD_STATISTICS
- PGXC_COMM_CLIENT_INFO
- PGXC_COMM_DELAY
- PGXC_COMM_RECV_STREAM
- PGXC_COMM_SEND_STREAM
- PGXC_COMM_STATUS
- PGXC_DEADLOCK
- PGXC_GET_STAT_ALL_TABLES
- PGXC_GET_STAT_ALL_PARTITIONS
- PGXC_GET_TABLE_SKEWNESS
- PGXC_GTM_SNAPSHOT_STATUS
- PGXC_INSTANCE_TIME
- PGXC_INSTR_UNIQUE_SQL
- PGXC_LOCK_CONFLICTS
- PGXC_NODE_ENV
- PGXC_NODE_STAT_RESET_TIME
- PGXC_OS_RUN_INFO
- PGXC_OS_THREADS
- PGXC_PREPARED_XACTS
- PGXC_REDO_STAT
- PGXC_REL_IOSTAT
- PGXC_REPLICATION_SLOTS
- PGXC_RUNNING_XACTS
- PGXC_SETTINGS
- PGXC_STAT_ACTIVITY
- PGXC_STAT_BAD_BLOCK
- PGXC_STAT_BGWRITER
- PGXC_STAT_DATABASE
- PGXC_STAT_REPLICATION
- PGXC_SQL_COUNT
- PGXC_THREAD_WAIT_STATUS
- PGXC_TOTAL_MEMORY_DETAIL
- PGXC_TOTAL_SCHEMA_INFO
- PGXC_TOTAL_SCHEMA_INFO_ANALYZE
- PGXC_USER_TRANSACTION
- PGXC_VARIABLE_INFO
- PGXC_WAIT_EVENTS
- PGXC_WLM_OPERATOR_HISTORY
- PGXC_WLM_OPERATOR_INFO
- PGXC_WLM_OPERATOR_STATISTICS
- PGXC_WLM_SESSION_INFO
- PGXC_WLM_SESSION_HISTORY
- PGXC_WLM_SESSION_STATISTICS
- PGXC_WLM_WORKLOAD_RECORDS
- PGXC_WORKLOAD_SQL_COUNT
- PGXC_WORKLOAD_SQL_ELAPSE_TIME
- PGXC_WORKLOAD_TRANSACTION
- PLAN_TABLE
- PLAN_TABLE_DATA
- PV_FILE_STAT
- PV_INSTANCE_TIME
- PV_OS_RUN_INFO
- PV_SESSION_MEMORY
- PV_SESSION_MEMORY_DETAIL
- PV_SESSION_STAT
- PV_SESSION_TIME
- PV_TOTAL_MEMORY_DETAIL
- PV_REDO_STAT
- REDACTION_COLUMNS
- REDACTION_POLICIES
- USER_COL_COMMENTS
- USER_CONSTRAINTS
- USER_CONS_COLUMNS
- USER_INDEXES
- USER_IND_COLUMNS
- USER_IND_EXPRESSIONS
- USER_IND_PARTITIONS
- USER_JOBS
- USER_OBJECTS
- USER_PART_INDEXES
- USER_PART_TABLES
- USER_PROCEDURES
- USER_SEQUENCES
- USER_SOURCE
- USER_SYNONYMS
- USER_TAB_COLUMNS
- USER_TAB_COMMENTS
- USER_TAB_PARTITIONS
- USER_TABLES
- USER_TRIGGERS
- USER_VIEWS
- V$SESSION
- V$SESSION_LONGOPS
-
GUC Parameters
- Viewing GUC Parameters
- Configuring GUC Parameters
- GUC Parameter Usage
- Connection and Authentication
- Resource Consumption
- Parallel Data Import
- Write Ahead Logs
- HA Replication
- Query Planning
- Error Reporting and Logging
- Alarm Detection
- Statistics During the Database Running
- Workload Management
- Automatic Cleanup
- Default Settings of Client Connection
- Lock Management
- Version and Platform Compatibility
- Fault Tolerance
- Connection Pool Parameters
- Cluster Transaction Parameters
- Developer Operations
- Auditing
- Transaction Monitoring
- Miscellaneous Parameters
- Glossary
-
SQL Syntax Reference (ME-Abu Dhabi Region)
- GaussDB(DWS) SQL
- Differences Between GaussDB(DWS) and PostgreSQL
- Keyword
- Data Types
- Constant and Macro
-
Functions and Operators
- Logical Operators
- Comparison Operators
- Character Processing Functions and Operators
- Binary String Functions and Operators
- Bit String Functions and Operators
- Pattern Matching Operators
- Mathematical Functions and Operators
- Date and Time Processing Functions and Operators
- Type Conversion Functions
- Geometric Functions and Operators
- Network Address Functions and Operators
- Text Search Functions and Operators
- UUID Functions
- JSON Functions
- HLL Functions and Operators
- SEQUENCE Functions
- Array Functions and Operators
- Range Functions and Operators
- Aggregate Functions
- Window Functions
- Security Functions
- Set Returning Functions
- Conditional Expression Functions
- System Information Functions
-
System Administration Functions
- Configuration Settings Functions
- Universal File Access Functions
- Server Signaling Functions
- Backup and Restoration Control Functions
- Snapshot Synchronization Functions
- Database Object Functions
- Advisory Lock Functions
- Residual File Management Functions
- Replication Functions
- Other Functions
- Resource Management Functions
- Data Redaction Functions
- Statistics Information Functions
- Trigger Functions
- XML Functions
- Call Stack Recording Functions
- Expressions
- Type Conversion
- Full Text Search
- System Operation
- Controlling Transactions
-
DDL Syntax
- DDL Syntax Overview
- ALTER DATABASE
- ALTER FOREIGN TABLE (for GDS)
- ALTER FOREIGN TABLE (for HDFS or OBS)
- ALTER FUNCTION
- ALTER GROUP
- ALTER INDEX
- ALTER LARGE OBJECT
- ALTER REDACTION POLICY
- ALTER RESOURCE POOL
- ALTER ROLE
- ALTER ROW LEVEL SECURITY POLICY
- ALTER SCHEMA
- ALTER SEQUENCE
- ALTER SERVER
- ALTER SESSION
- ALTER SYNONYM
- ALTER SYSTEM KILL SESSION
- ALTER TABLE
- ALTER TABLE PARTITION
- ALTER TEXT SEARCH CONFIGURATION
- ALTER TEXT SEARCH DICTIONARY
- ALTER TRIGGER
- ALTER TYPE
- ALTER USER
- ALTER VIEW
- CLEAN CONNECTION
- CLOSE
- CLUSTER
- COMMENT
- CREATE BARRIER
- CREATE DATABASE
- CREATE FOREIGN TABLE (for GDS Import and Export)
- CREATE FOREIGN TABLE (for OBS Import and Export)
- CREATE FOREIGN TABLE (SQL on Hadoop or OBS)
- CREATE FUNCTION
- CREATE GROUP
- CREATE INDEX
- CREATE REDACTION POLICY
- CREATE ROW LEVEL SECURITY POLICY
- CREATE PROCEDURE
- CREATE RESOURCE POOL
- CREATE ROLE
- CREATE SCHEMA
- CREATE SEQUENCE
- CREATE SERVER
- CREATE SYNONYM
- CREATE TABLE
- CREATE TABLE AS
- CREATE TABLE PARTITION
- CREATE TABLESPACE
- CREATE TEXT SEARCH CONFIGURATION
- CREATE TEXT SEARCH DICTIONARY
- CREATE TRIGGER
- CREATE TYPE
- CREATE USER
- CREATE VIEW
- CURSOR
- DROP DATABASE
- DROP FOREIGN TABLE
- DROP FUNCTION
- DROP GROUP
- DROP INDEX
- DROP OWNED
- DROP REDACTION POLICY
- DROP ROW LEVEL SECURITY POLICY
- DROP PROCEDURE
- DROP RESOURCE POOL
- DROP ROLE
- DROP SCHEMA
- DROP SEQUENCE
- DROP SERVER
- DROP SYNONYM
- DROP TABLE
- DROP TABLESPACE
- DROP TEXT SEARCH CONFIGURATION
- DROP TEXT SEARCH DICTIONARY
- DROP TRIGGER
- DROP TYPE
- DROP USER
- DROP VIEW
- FETCH
- MOVE
- REINDEX
- RESET
- SET
- SET CONSTRAINTS
- SET ROLE
- SET SESSION AUTHORIZATION
- SHOW
- TRUNCATE
- VACUUM
- DML Syntax
- DCL Syntax
- DQL Syntax
- TCL Syntax
- GIN Indexes
-
Tool Guide (ME-Abu Dhabi Region)
- Overview
- Downloading Client Tools
- gsql - CLI Client
-
Data Studio - Integrated Database Development Tool
- About Data Studio
- Installing and Configuring Data Studio
- Quick Start
- Data Studio GUI
- Data Studio Menus
- Data Studio Toolbar
- Data Studio Right-Click Menus
- Connection Profiles
- Databases
- Schemas
- Creating a Function/Procedure
- Editing a Function/Procedure
- Granting/Revoking a Permission (Function/Procedure)
- Debugging a PL/SQL Function
- Working with Functions/Procedures
- GaussDB(DWS) Tables
- Sequences
- Views
-
SQL Terminal
- Opening Multiple SQL Terminal Tabs
- Managing the History of Executed SQL Queries
- Opening and Saving SQL Scripts
- Viewing Object Properties in the SQL Terminal
- Canceling the Execution of SQL Queries
- Formatting of SQL Queries
- Selecting a DB Object in the SQL Terminal
- Viewing the Execution Plan and Costs
- Viewing the Query Execution Plan and Cost Graphically
- Using SQL Terminals
- Exporting Query Results
- Managing SQL Terminal Connections
- Batch Operation
- Personalizing Data Studio
- Performance Specifications
- Security Management
- Troubleshooting
- FAQs
- GDS: Parallel Data Loader
-
DSC: SQL Syntax Migration Tool
- Overview
- Supported Keywords and Features
- Constraints and Limitations
- System Requirements
- Installing DSC
- Configuring DSC
- Using DSC
- Teradata Syntax Migration
-
Oracle Syntax Migration
- Overview
- Schema Objects
- COMPRESS Phrase
- Bitmap Index
- Custom Tablespace
- Supplemental Log Data
- LONG RAW
- DML
- Pseudo Columns
- OUTER JOIN
- OUTER QUERY (+)
- CONNECT BY
- System Functions
- PL/SQL
- PL/SQL Collections (Using User-Defined Types)
- PL/SQL Packages
- VARRAY
- Granting Execution Permissions
- Package Name List
- Data Type
- Chinese Character Support
- Netezza Syntax Migration
- MySQL Syntax Migration
- DB2 Syntax Migration
- Command Reference
- Log Reference
- Troubleshooting
- FAQs
- Security Management
- Server Tool
- Error Code Reference (ME-Abu Dhabi Region)
-
User Guide (Paris Region)
- Service Overview
- Getting Started
- Process for Using GaussDB(DWS)
- Preparations
- Creating or Deleting a Cluster
-
Cluster Connection
- Methods of Connecting to a Cluster
- Obtaining the Cluster Connection Address
- Using the Data Studio GUI Client to Connect to a Cluster
- Using the gsql CLI Client to Connect to a Cluster
- Using the JDBC and ODBC Drivers to Connect to a Cluster
- Using the Third-Party Function Library psycopg2 of Python to Connect to a Cluster
- Using the Python Library PyGreSQL to Connect to a Cluster
- Managing Database Connections
- Monitoring and Alarms
- Specifications Change and Scaling
- Backup and Disaster Recovery
- Intelligent O&M
-
Cluster Management
- Modifying Database Parameters
- Checking the Cluster Status
- Viewing Cluster Details
- Managing Access Domain Names
- Cluster Topology
- Managing Tags
- Managing Enterprise Projects
- Managing Clusters That Fail to Be Created
- Removing the Read-only Status
- Performing a Primary/Standby Switchback
- Cluster Restart
- Resetting a Password
- Cluster Upgrade
- Associating and Disassociating ELB
- Managing CNs
- Cluster Log Management
- Database User Management
- Audit Logs
- Cluster Security Management
- Resource Management
- Data Source Management
-
Managing Logical Clusters
- Logical Cluster Overview
- Adding Logical Clusters
- Editing Logical Clusters
- Managing Resources (in a Logical Cluster)
- Restarting Logical Clusters
- Scaling Out Logical Clusters
- Deleting Logical Clusters
- Tutorial: Converting a Physical Cluster That Contains Data into a Logical Cluster
- Tutorial: Dividing a New Physical Cluster into Logical Clusters
-
FAQs
-
General Problems
- Why Do I Need to Use a Data Warehouse?
- What Are the Differences Between Users and Roles?
- When Should I Use GaussDB(DWS) and MRS?
- How Do I Check the Creation Time of a Database User?
- Regions and AZs
- Is My Data Secure in GaussDB(DWS)?
- How Is GaussDB(DWS) Secured?
- Can I Modify the Security Group of a GaussDB(DWS) Cluster?
- How Are Dirty Pages Generated in GaussDB(DWS)?
-
Database Usage
- How Do I Change Distribution Columns?
- How Do I View and Set the Database Character Encoding?
- What Do I Do If Date Type Is Automatically Converted to the Timestamp Type During Table Creation?
- Do I Need to Run VACUUM FULL and ANALYZE on Common Tables Periodically?
- Do I Need to Set a Distribution Key After Setting a Primary Key?
- Is GaussDB(DWS) Compatible with PostgreSQL Stored Procedures?
- What Are Partitioned Tables, Partitions, and Partition Keys?
- How Can I Export the Table Structure?
- How Do I Delete Table Data Efficiently?
- How Do I View Foreign Table Information?
- If No Distribution Column Is Specified, How Will Data Be Stored?
- How Do I Replace the Null Result with 0?
- How Do I Check Whether a Table Is Row-Stored or Column-Stored?
- How Do I Query the Information About GaussDB(DWS) Column-Store Tables?
- Why Sometimes the GaussDB(DWS) Query Indexes Become Invalid?
- How Do I Use a User-Defined Function to Rewrite the CRC32() Function?
- What Are the Schemas Starting with pg_toast_temp* or pg_temp*?
- Solutions to Inconsistent GaussDB(DWS) Query Results
- Which System Catalogs That the VACUUM FULL Operation Cannot Be Performed on?
- In Which Scenarios Would a Statement Be "idle in transaction"?
- How Does GaussDB(DWS) Implement Row-to-Column and Column-to-Row Conversion?
- What Are the Differences Between Unique Constraints and Unique Indexes?
- What Are the Differences Between Functions and Stored Procedures?
- How Do I Delete Duplicate Table Data?
-
Cluster Management
- What Do I Do If Creating a GaussDB(DWS) Cluster Failed?
- How Can I Clear and Reclaim the Storage Space?
- Why Did the Used Storage Shrink After Scale-out?
- How Do I View Node Metrics (CPU, Memory, and Disk Usage)?
- How Is the Disk Space or Capacity of GaussDB(DWS) Calculated?
- What Are the gaussdb and postgres Databases of GaussDB(DWS)?
- How Do I Set the Maximum Number of Sessions When Adding an Alarm Rule on Cloud Eye?
- When Should I Add CNs or Scale out a cluster?
- How Should I Select from a Small-Flavor Many-Node Cluster and a Large-Flavor Three-Node Cluster with Same CPU Cores and Memory?
- What Are the Differences Between Hot Data Storage and Cold Data Storage?
- What Do I do if the Scale-in Button Is Dimmed?
-
Database Connections
- How Applications Communicate with GaussDB(DWS)?
- Does GaussDB(DWS) Support Third-Party Clients and JDBC and ODBC Drivers?
- Can I Connect to GaussDB(DWS) Cluster Nodes Using SSH?
- What Should I Do If I Cannot Connect to a GaussDB(DWS) Cluster?
- Why Was I Not Notified of Failure Unbinding the EIP When GaussDB(DWS) Is Connected Over the Internet?
- How Do I Configure a Whitelist to Protect Clusters Available Through a Public IP Address?
-
Data Import and Export
- What Are the Differences Between Data Formats Supported by OBS and GDS Foreign Tables?
- How Do I Import Incremental Data Using an OBS Foreign Table?
- How Can I Import Data to GaussDB(DWS)?
- How Much Service Data Can a Data Warehouse Store?
- How Do I Use \Copy to Import and Export Data?
- How Do I Implement Fault Tolerance Import Between Different Encoding Libraries
- Can I Import and Export Data to and from OBS Across Regions?
- Can I Import Data over the Public/External Network Using GDS?
- Which Are the Factors That Affect GaussDB(DWS) Import Performance?
-
Account, Password, and Permission
- How Does GaussDB(DWS) Implement Workload Isolation?
- How Do I Change the Password of a Database Account When the Password Expires?
- How Do I Grant Table Permissions to a User?
- How Do I Grant Schema Permissions to a User?
- How Do I Create a Database Read-only User?
- How Do I Create Private Database Users and Tables?
- How Do I Revoke the CONNECT ON DATABASE Permission from a User?
- How Do I View the Table Permissions of a User?
- Who Is User Ruby?
-
Database Performance
- Why Is SQL Execution Slow After Long GaussDB(DWS) Usage?
- Why Does GaussDB(DWS) Perform Worse Than a Single-Server Database in Extreme Scenarios?
- How Can I View SQL Execution Records in a Certain Period When Read and Write Requests Are Blocked?
- What Do I Do If My Cluster Is Unavailable Because of Insufficient Space?
- GaussDB(DWS) CPU Resource Management
- Why the Tasks Executed by an Ordinary User Are Slower Than That Executed by the dbadmin User?
- What Are the Factors Related to the Single-Table Query Performance in GaussDB(DWS)?
- Snapshot Backup and Restoration
-
General Problems
- API Reference (Paris Region)
-
Developer Guide (Paris Region)
- Welcome
- System Overview
-
Data Migration
- Data Migration to GaussDB(DWS)
-
Data Import
- Importing Data from OBS in Parallel
- Using GDS to Import Data from a Remote Server
- Importing Data from MRS to a Cluster
- Importing Data from One GaussDB(DWS) Cluster to Another
- Using a gsql Meta-Command to Import Data
- Running the COPY FROM STDIN Statement to Import Data
- Full Database Migration
- Meta-command Migration
- Data Export
- Other Operations
- Syntax Compatibility Differences Among Oracle, Teradata, and MySQL
- Database Security Management
- Development and Design Proposal
-
Guide: JDBC- or ODBC-Based Development
- Development Specifications
- Downloading Drivers
-
JDBC-Based Development
- JDBC Package and Driver Class
- Development Process
- Loading a Driver
- Connecting to a Database
- Executing SQL Statements
- Processing Data in a Result Set
- Closing the Connection
- Example: Common Operations
- Example: Retrying SQL Queries for Applications
- Example: Importing and Exporting Data Through Local Files
- Example: Migrating Data from MySQL to GaussDB(DWS)
-
JDBC Interface Reference
- java.sql.Connection
- java.sql.CallableStatement
- java.sql.DatabaseMetaData
- java.sql.Driver
- java.sql.PreparedStatement
- java.sql.ResultSet
- java.sql.ResultSetMetaData
- java.sql.Statement
- javax.sql.ConnectionPoolDataSource
- javax.sql.DataSource
- javax.sql.PooledConnection
- javax.naming.Context
- javax.naming.spi.InitialContextFactory
- CopyManager
- ODBC-Based Development
- PostGIS Extension
- Resource Load Management
- Resource Monitoring
-
Query Performance Optimization
- Overview of Query Performance Optimization
- Query Analysis
- Query Improvement
-
Optimization Cases
- Case: Selecting an Appropriate Distribution Column
- Case: Creating an Appropriate Index
- Case: Adding NOT NULL for JOIN Columns
- Case: Pushing Down Sort Operations to DNs
- Case: Configuring cost_param for Better Query Performance
- Case: Adjusting the Distribution Key
- Case: Adjusting the Partial Clustering Key
- Case: Adjusting the Table Storage Mode in a Medium Table
- Case: Adjusting the Local Clustering Column
- Case: Reconstructing Partition Tables
- Case: Adjusting the GUC Parameter best_agg_plan
- Case: Rewriting SQL and Deleting Subqueries (Case 1)
- Case: Rewriting SQL and Deleting Subqueries (Case 2)
- Case: Rewriting SQL Statements and Eliminating Prune Interference
- Case: Rewriting SQL Statements and Deleting in-clause
- Case: Setting Partial Cluster Keys
- SQL Execution Troubleshooting
- Common Performance Parameter Optimization Design
- User-Defined Functions
- Stored Procedures
-
System Catalogs and System Views
- Overview of System Catalogs and System Views
-
System Catalogs
- GS_OBSSCANINFO
- GS_WLM_INSTANCE_HISTORY
- GS_WLM_OPERATOR_INFO
- GS_WLM_SESSION_INFO
- GS_WLM_USER_RESOURCE_HISTORY
- PG_AGGREGATE
- PG_AM
- PG_AMOP
- PG_AMPROC
- PG_ATTRDEF
- PG_ATTRIBUTE
- PG_AUTHID
- PG_AUTH_HISTORY
- PG_AUTH_MEMBERS
- PG_CAST
- PG_CLASS
- PG_COLLATION
- PG_CONSTRAINT
- PG_CONVERSION
- PG_DATABASE
- PG_DB_ROLE_SETTING
- PG_DEFAULT_ACL
- PG_DEPEND
- PG_DESCRIPTION
- PG_ENUM
- PG_EXTENSION
- PG_EXTENSION_DATA_SOURCE
- PG_FOREIGN_DATA_WRAPPER
- PG_FOREIGN_SERVER
- PG_FOREIGN_TABLE
- PG_INDEX
- PG_INHERITS
- PG_JOBS
- PG_LANGUAGE
- PG_LARGEOBJECT
- PG_LARGEOBJECT_METADATA
- PG_NAMESPACE
- PG_OBJECT
- PG_OBSSCANINFO
- PG_OPCLASS
- PG_OPERATOR
- PG_OPFAMILY
- PG_PARTITION
- PG_PLTEMPLATE
- PG_PROC
- PG_RANGE
- PG_REDACTION_COLUMN
- PG_REDACTION_POLICY
- PG_RLSPOLICY
- PG_RESOURCE_POOL
- PG_REWRITE
- PG_SECLABEL
- PG_SHDEPEND
- PG_SHDESCRIPTION
- PG_SHSECLABEL
- PG_STATISTIC
- PG_STATISTIC_EXT
- PG_SYNONYM
- PG_TABLESPACE
- PG_TRIGGER
- PG_TS_CONFIG
- PG_TS_CONFIG_MAP
- PG_TS_DICT
- PG_TS_PARSER
- PG_TS_TEMPLATE
- PG_TYPE
- PG_USER_MAPPING
- PG_USER_STATUS
- PG_WORKLOAD_ACTION
- PGXC_CLASS
- PGXC_GROUP
- PGXC_NODE
-
System Views
- ALL_ALL_TABLES
- ALL_CONSTRAINTS
- ALL_CONS_COLUMNS
- ALL_COL_COMMENTS
- ALL_DEPENDENCIES
- ALL_IND_COLUMNS
- ALL_IND_EXPRESSIONS
- ALL_INDEXES
- ALL_OBJECTS
- ALL_PROCEDURES
- ALL_SEQUENCES
- ALL_SOURCE
- ALL_SYNONYMS
- ALL_TAB_COLUMNS
- ALL_TAB_COMMENTS
- ALL_TABLES
- ALL_USERS
- ALL_VIEWS
- DBA_DATA_FILES
- DBA_USERS
- DBA_COL_COMMENTS
- DBA_CONSTRAINTS
- DBA_CONS_COLUMNS
- DBA_IND_COLUMNS
- DBA_IND_EXPRESSIONS
- DBA_IND_PARTITIONS
- DBA_INDEXES
- DBA_OBJECTS
- DBA_PART_INDEXES
- DBA_PART_TABLES
- DBA_PROCEDURES
- DBA_SEQUENCES
- DBA_SOURCE
- DBA_SYNONYMS
- DBA_TAB_COLUMNS
- DBA_TAB_COMMENTS
- DBA_TAB_PARTITIONS
- DBA_TABLES
- DBA_TABLESPACES
- DBA_TRIGGERS
- DBA_VIEWS
- DUAL
- GLOBAL_REDO_STAT
- GLOBAL_REL_IOSTAT
- GLOBAL_STAT_DATABASE
- GLOBAL_WORKLOAD_SQL_COUNT
- GLOBAL_WORKLOAD_SQL_ELAPSE_TIME
- GLOBAL_WORKLOAD_TRANSACTION
- GS_ALL_CONTROL_GROUP_INFO
- GS_CLUSTER_RESOURCE_INFO
- GS_INSTR_UNIQUE_SQL
- GS_REL_IOSTAT
- GS_NODE_STAT_RESET_TIME
- GS_SESSION_CPU_STATISTICS
- GS_SESSION_MEMORY_STATISTICS
- GS_SQL_COUNT
- GS_WAIT_EVENTS
- GS_WLM_OPERAROR_INFO
- GS_WLM_OPERATOR_HISTORY
- GS_WLM_OPERATOR_STATISTICS
- GS_WLM_SESSION_INFO
- GS_WLM_SESSION_HISTORY
- GS_WLM_SESSION_STATISTICS
- GS_WLM_SQL_ALLOW
- GS_WORKLOAD_SQL_COUNT
- GS_WORKLOAD_SQL_ELAPSE_TIME
- GS_WORKLOAD_TRANSACTION
- GS_STAT_DB_CU
- GS_STAT_SESSION_CU
- GS_TOTAL_NODEGROUP_MEMORY_DETAIL
- GS_USER_TRANSACTION
- GS_VIEW_DEPENDENCY
- GS_VIEW_DEPENDENCY_PATH
- GS_VIEW_INVALID
- PG_AVAILABLE_EXTENSION_VERSIONS
- PG_AVAILABLE_EXTENSIONS
- PG_BULKLOAD_STATISTICS
- PG_COMM_CLIENT_INFO
- PG_COMM_DELAY
- PG_COMM_STATUS
- PG_COMM_RECV_STREAM
- PG_COMM_SEND_STREAM
- PG_CONTROL_GROUP_CONFIG
- PG_CURSORS
- PG_EXT_STATS
- PG_GET_INVALID_BACKENDS
- PG_GET_SENDERS_CATCHUP_TIME
- PG_GROUP
- PG_INDEXES
- PG_JOB
- PG_JOB_PROC
- PG_JOB_SINGLE
- PG_LIFECYCLE_DATA_DISTRIBUTE
- PG_LOCKS
- PG_NODE_ENV
- PG_OS_THREADS
- PG_POOLER_STATUS
- PG_PREPARED_STATEMENTS
- PG_PREPARED_XACTS
- PG_QUERYBAND_ACTION
- PG_REPLICATION_SLOTS
- PG_ROLES
- PG_RULES
- PG_RUNNING_XACTS
- PG_SECLABELS
- PG_SESSION_WLMSTAT
- PG_SESSION_IOSTAT
- PG_SETTINGS
- PG_SHADOW
- PG_SHARED_MEMORY_DETAIL
- PG_STATS
- PG_STAT_ACTIVITY
- PG_STAT_ALL_INDEXES
- PG_STAT_ALL_TABLES
- PG_STAT_BAD_BLOCK
- PG_STAT_BGWRITER
- PG_STAT_DATABASE
- PG_STAT_DATABASE_CONFLICTS
- PG_STAT_GET_MEM_MBYTES_RESERVED
- PG_STAT_USER_FUNCTIONS
- PG_STAT_USER_INDEXES
- PG_STAT_USER_TABLES
- PG_STAT_REPLICATION
- PG_STAT_SYS_INDEXES
- PG_STAT_SYS_TABLES
- PG_STAT_XACT_ALL_TABLES
- PG_STAT_XACT_SYS_TABLES
- PG_STAT_XACT_USER_FUNCTIONS
- PG_STAT_XACT_USER_TABLES
- PG_STATIO_ALL_INDEXES
- PG_STATIO_ALL_SEQUENCES
- PG_STATIO_ALL_TABLES
- PG_STATIO_SYS_INDEXES
- PG_STATIO_SYS_SEQUENCES
- PG_STATIO_SYS_TABLES
- PG_STATIO_USER_INDEXES
- PG_STATIO_USER_SEQUENCES
- PG_STATIO_USER_TABLES
- PG_THREAD_WAIT_STATUS
- PG_TABLES
- PG_TIMEZONE_ABBREVS
- PG_TIMEZONE_NAMES
- PG_TOTAL_MEMORY_DETAIL
- PG_TOTAL_SCHEMA_INFO
- PG_TOTAL_USER_RESOURCE_INFO
- PG_USER
- PG_USER_MAPPINGS
- PG_VIEWS
- PG_WLM_STATISTICS
- PGXC_BULKLOAD_PROGRESS
- PGXC_BULKLOAD_STATISTICS
- PGXC_COMM_CLIENT_INFO
- PGXC_COMM_DELAY
- PGXC_COMM_RECV_STREAM
- PGXC_COMM_SEND_STREAM
- PGXC_COMM_STATUS
- PGXC_DEADLOCK
- PGXC_GET_STAT_ALL_TABLES
- PGXC_GET_STAT_ALL_PARTITIONS
- PGXC_GET_TABLE_SKEWNESS
- PGXC_GTM_SNAPSHOT_STATUS
- PGXC_INSTANCE_TIME
- PGXC_INSTR_UNIQUE_SQL
- PGXC_LOCK_CONFLICTS
- PGXC_NODE_ENV
- PGXC_NODE_STAT_RESET_TIME
- PGXC_OS_RUN_INFO
- PGXC_OS_THREADS
- PGXC_PREPARED_XACTS
- PGXC_REDO_STAT
- PGXC_REL_IOSTAT
- PGXC_REPLICATION_SLOTS
- PGXC_RUNNING_XACTS
- PGXC_SETTINGS
- PGXC_STAT_ACTIVITY
- PGXC_STAT_BAD_BLOCK
- PGXC_STAT_BGWRITER
- PGXC_STAT_DATABASE
- PGXC_STAT_REPLICATION
- PGXC_SQL_COUNT
- PGXC_THREAD_WAIT_STATUS
- PGXC_TOTAL_MEMORY_DETAIL
- PGXC_TOTAL_SCHEMA_INFO
- PGXC_TOTAL_SCHEMA_INFO_ANALYZE
- PGXC_USER_TRANSACTION
- PGXC_VARIABLE_INFO
- PGXC_WAIT_EVENTS
- PGXC_WLM_OPERATOR_HISTORY
- PGXC_WLM_OPERATOR_INFO
- PGXC_WLM_OPERATOR_STATISTICS
- PGXC_WLM_SESSION_INFO
- PGXC_WLM_SESSION_HISTORY
- PGXC_WLM_SESSION_STATISTICS
- PGXC_WLM_WORKLOAD_RECORDS
- PGXC_WORKLOAD_SQL_COUNT
- PGXC_WORKLOAD_SQL_ELAPSE_TIME
- PGXC_WORKLOAD_TRANSACTION
- PLAN_TABLE
- PLAN_TABLE_DATA
- PV_FILE_STAT
- PV_INSTANCE_TIME
- PV_OS_RUN_INFO
- PV_SESSION_MEMORY
- PV_SESSION_MEMORY_DETAIL
- PV_SESSION_STAT
- PV_SESSION_TIME
- PV_TOTAL_MEMORY_DETAIL
- PV_REDO_STAT
- REDACTION_COLUMNS
- REDACTION_POLICIES
- USER_COL_COMMENTS
- USER_CONSTRAINTS
- USER_CONS_COLUMNS
- USER_INDEXES
- USER_IND_COLUMNS
- USER_IND_EXPRESSIONS
- USER_IND_PARTITIONS
- USER_JOBS
- USER_OBJECTS
- USER_PART_INDEXES
- USER_PART_TABLES
- USER_PROCEDURES
- USER_SEQUENCES
- USER_SOURCE
- USER_SYNONYMS
- USER_TAB_COLUMNS
- USER_TAB_COMMENTS
- USER_TAB_PARTITIONS
- USER_TABLES
- USER_TRIGGERS
- USER_VIEWS
- V$SESSION
- V$SESSION_LONGOPS
-
GUC Parameters
- Viewing GUC Parameters
- Configuring GUC Parameters
- GUC Parameter Usage
- Connection and Authentication
- Resource Consumption
- Parallel Data Import
- Write Ahead Logs
- HA Replication
- Query Planning
- Error Reporting and Logging
- Alarm Detection
- Statistics During the Database Running
- Workload Management
- Automatic Cleanup
- Default Settings of Client Connection
- Lock Management
- Version and Platform Compatibility
- Fault Tolerance
- Connection Pool Parameters
- Cluster Transaction Parameters
- Developer Operations
- Auditing
- Transaction Monitoring
- Miscellaneous Parameters
- Glossary
-
SQL Syntax Reference (Paris Region)
- GaussDB(DWS) SQL
- Differences Between GaussDB(DWS) and PostgreSQL
- Keyword
- Data Types
- Constant and Macro
-
Functions and Operators
- Logical Operators
- Comparison Operators
- Character Processing Functions and Operators
- Binary String Functions and Operators
- Bit String Functions and Operators
- Pattern Matching Operators
- Mathematical Functions and Operators
- Date and Time Processing Functions and Operators
- Type Conversion Functions
- Geometric Functions and Operators
- Network Address Functions and Operators
- Text Search Functions and Operators
- UUID Functions
- JSON Functions
- HLL Functions and Operators
- SEQUENCE Functions
- Array Functions and Operators
- Range Functions and Operators
- Aggregate Functions
- Window Functions
- Security Functions
- Set Returning Functions
- Conditional Expression Functions
- System Information Functions
-
System Administration Functions
- Configuration Settings Functions
- Universal File Access Functions
- Server Signaling Functions
- Backup and Restoration Control Functions
- Snapshot Synchronization Functions
- Database Object Functions
- Advisory Lock Functions
- Residual File Management Functions
- Replication Functions
- Other Functions
- Resource Management Functions
- Data Redaction Functions
- Statistics Information Functions
- Trigger Functions
- XML Functions
- Call Stack Recording Functions
- Expressions
- Type Conversion
- Full Text Search
- System Operation
- Controlling Transactions
-
DDL Syntax
- DDL Syntax Overview
- ALTER DATABASE
- ALTER FOREIGN TABLE (for GDS)
- ALTER FOREIGN TABLE (for HDFS or OBS)
- ALTER FUNCTION
- ALTER GROUP
- ALTER INDEX
- ALTER LARGE OBJECT
- ALTER REDACTION POLICY
- ALTER RESOURCE POOL
- ALTER ROLE
- ALTER ROW LEVEL SECURITY POLICY
- ALTER SCHEMA
- ALTER SEQUENCE
- ALTER SERVER
- ALTER SESSION
- ALTER SYNONYM
- ALTER SYSTEM KILL SESSION
- ALTER TABLE
- ALTER TABLE PARTITION
- ALTER TEXT SEARCH CONFIGURATION
- ALTER TEXT SEARCH DICTIONARY
- ALTER TRIGGER
- ALTER TYPE
- ALTER USER
- ALTER VIEW
- CLEAN CONNECTION
- CLOSE
- CLUSTER
- COMMENT
- CREATE BARRIER
- CREATE DATABASE
- CREATE FOREIGN TABLE (for GDS Import and Export)
- CREATE FOREIGN TABLE (SQL on OBS or Hadoop )
- CREATE FOREIGN TABLE (for OBS Import and Export)
- CREATE FUNCTION
- CREATE GROUP
- CREATE INDEX
- CREATE REDACTION POLICY
- CREATE ROW LEVEL SECURITY POLICY
- CREATE PROCEDURE
- CREATE RESOURCE POOL
- CREATE ROLE
- CREATE SCHEMA
- CREATE SEQUENCE
- CREATE SERVER
- CREATE SYNONYM
- CREATE TABLE
- CREATE TABLE AS
- CREATE TABLE PARTITION
- CREATE TABLESPACE
- CREATE TEXT SEARCH CONFIGURATION
- CREATE TEXT SEARCH DICTIONARY
- CREATE TRIGGER
- CREATE TYPE
- CREATE USER
- CREATE VIEW
- CURSOR
- DROP DATABASE
- DROP FOREIGN TABLE
- DROP FUNCTION
- DROP GROUP
- DROP INDEX
- DROP OWNED
- DROP REDACTION POLICY
- DROP ROW LEVEL SECURITY POLICY
- DROP PROCEDURE
- DROP RESOURCE POOL
- DROP ROLE
- DROP SCHEMA
- DROP SEQUENCE
- DROP SERVER
- DROP SYNONYM
- DROP TABLE
- DROP TABLESPACE
- DROP TEXT SEARCH CONFIGURATION
- DROP TEXT SEARCH DICTIONARY
- DROP TRIGGER
- DROP TYPE
- DROP USER
- DROP VIEW
- FETCH
- MOVE
- REINDEX
- RESET
- SET
- SET CONSTRAINTS
- SET ROLE
- SET SESSION AUTHORIZATION
- SHOW
- TRUNCATE
- VACUUM
- DML Syntax
- DCL Syntax
- DQL Syntax
- TCL Syntax
- GIN Indexes
-
Tool Guide (Paris Region)
- Overview
- Downloading Client Tools
- gsql - CLI Client
-
Data Studio - Integrated Database Development Tool
- About Data Studio
- Installing and Configuring Data Studio
- Quick Start
- Data Studio GUI
- Data Studio Menus
- Data Studio Toolbar
- Data Studio Right-Click Menus
- Connection Profiles
- Databases
- Schemas
- Creating a Function/Procedure
- Editing a Function/Procedure
- Granting/Revoking a Permission (Function/Procedure)
- Debugging a PL/SQL Function
- Working with Functions/Procedures
- GaussDB(DWS) Tables
- Sequences
- Views
-
SQL Terminal
- Opening Multiple SQL Terminal Tabs
- Managing the History of Executed SQL Queries
- Opening and Saving SQL Scripts
- Viewing Object Properties in the SQL Terminal
- Canceling the Execution of SQL Queries
- Formatting of SQL Queries
- Selecting a DB Object in the SQL Terminal
- Viewing the Execution Plan and Costs
- Viewing the Query Execution Plan and Cost Graphically
- Using SQL Terminals
- Exporting Query Results
- Managing SQL Terminal Connections
- Batch Operation
- Personalizing Data Studio
- Performance Specifications
- Security Management
- Troubleshooting
- FAQs
- GDS: Parallel Data Loader
-
DSC: SQL Syntax Migration Tool
- Overview
- Supported Keywords and Features
- Constraints and Limitations
- System Requirements
- Installing DSC
- Configuring DSC
- Using DSC
- Teradata Syntax Migration
-
Oracle Syntax Migration
- Overview
- Schema Objects
- COMPRESS Phrase
- Bitmap Index
- Custom Tablespace
- Supplemental Log Data
- LONG RAW
- DML
- Pseudo Columns
- OUTER JOIN
- OUTER QUERY (+)
- CONNECT BY
- System Functions
- PL/SQL
- PL/SQL Collections (Using User-Defined Types)
- PL/SQL Packages
- VARRAY
- Granting Execution Permissions
- Package Name List
- Data Type
- Chinese Character Support
- Netezza Syntax Migration
- MySQL Syntax Migration
- DB2 Syntax Migration
- Command Reference
- Log Reference
- Troubleshooting
- FAQs
- Security Management
- Server Tool
- Change History
- Error Code Reference (Paris Region)
-
User Guide (Kuala Lumpur Region)
- Service Overview
- Getting Started
- Process for Using GaussDB(DWS)
- Preparations
- Cluster Configuration
-
Cluster Connection
- Methods of Connecting to a Cluster
- Obtaining the Cluster Connection Address
- Using the gsql CLI Client to Connect to a Cluster
- Using the Data Studio GUI Client to Connect to a Cluster
- Using the JDBC and ODBC Drivers to Connect to a Cluster
- Using the Python Library psycopg2 to Connect to a Cluster
- Using the Python Library PyGreSQL to Connect to a Cluster
- Managing Database Connections
-
Clusters
- Checking the Cluster Status
- Viewing Basic Cluster Information
- Managing Access Domain Names
- Nodes
- Cluster Scale-out
- Cluster Redistribution
- Performing a Primary/Standby Switchback
- Cluster Upgrade
- Password Reset
- Cluster Restart
- Modifying Database Parameters
- MRS Data Sources
- Managing Cluster Workloads
- Managing Logical Clusters
- Managing Tags
- Deleting Clusters
- Managing Parameter Templates
- Managing Clusters That Fail to Be Created
- Read-only Status
- Cluster HA
- Monitoring and Alarms
- Cluster Security Management
- Audit Logs
-
FAQs
-
General Problems
- Why Are Data Warehouses Necessary?
- What Are the Differences Between a Data Warehouse and the Hadoop Big Data Platform?
- Why Should I Use GaussDB(DWS)?
- When Should I Use GaussDB(DWS) and MRS?
- What Are the Differences Between GaussDB(DWS) and Hive in Functions?
- What Is the User Quota?
- What Are the Differences Between Users and Roles?
- How Do I Check the Creation Time of a Database User?
- Regions and AZs
- Is My Data Secure in GaussDB(DWS)?
- How Is GaussDB(DWS) Secured?
- Can I Modify the Security Group of a GaussDB(DWS) Cluster?
- What Is a Database/Data Warehouse/Data Lake/Lakehouse?
-
Cluster Management
- What Do I Do If Creating a GaussDB(DWS) Cluster Failed?
- How Can I Clear and Reclaim the Storage Space?
- Why Did the Used Storage Shrink After Scale-out?
- How Do I View Node Metrics (CPU, Memory, and Disk Usage)?
- Does GaussDB(DWS) Support a Single Node for a Learning Environment?
- How Is the Disk Space or Capacity of GaussDB(DWS) Calculated?
- What Are the gaussdb and postgres Databases of GaussDB(DWS)?
- How Do I Set the Maximum Number of Sessions When Adding an Alarm Rule on Cloud Eye?
- When Should I Add CNs or Scale out a cluster?
- What Are the Differences Between Hot Data Storage and Cold Data Storage?
-
Database Connections
- How Applications Communicate with GaussDB(DWS)?
- Does GaussDB(DWS) Support Third-Party Clients and JDBC and ODBC Drivers?
- Can I Connect to GaussDB(DWS) Cluster Nodes Using SSH?
- What Should I Do If I Cannot Connect to a Data Warehouse Cluster?
- Why Was I Not Notified of Failure Unbinding the EIP When GaussDB(DWS) Is Connected Over the Internet?
- How Do I Configure a Whitelist to Protect Clusters Available Through a Public IP Address?
-
Data Import and Export
- What Are the Differences Between Data Formats Supported by OBS and GDS Foreign Tables?
- How Do I Import Incremental Data Using an OBS Foreign Table?
- How Can I Import Data to GaussDB(DWS)?
- How Much Service Data Can a Data Warehouse Store?
- How Do I Use \Copy to Import and Export Data?
- Can I Export GaussDB(DWS) Data from/to OBS Across Regions?
- How Do I Import GaussDB(DWS)/Oracle/MySQL/SQL Server Data to GaussDB(DWS) (Whole Database Migration)?
- Can I Import Data over the Public/External Network Using GDS?
- Which Are the Factors That Affect GaussDB(DWS) Import Performance?
-
Account, Password, and Permissions
- How Does GaussDB(DWS) Implement Workload Isolation?
- How Do I Change the Password of a Database Account When the Password Expires?
- How Do I Grant Table Permissions to a User?
- How Do I Grant Schema Permissions to a User?
- How Do I Create a Database Read-only User?
- How Do I Create Private Database Users and Tables?
- How Do I Revoke the CONNECT ON DATABASE Permission from a User?
- How Do I View the Table Permissions of a User?
- Who Is User Ruby?
-
Database Usage
- How Do I Change Distribution Columns?
- How Do I View and Set the Database Character Encoding?
- What Do I Do If Date Type Is Automatically Converted to the Timestamp Type During Table Creation?
- Do I Need to Run VACUUM FULL and ANALYZE on Common Tables Periodically?
- Do I Need to Set a Distribution Key After Setting a Primary Key?
- Is GaussDB(DWS) Compatible with PostgreSQL Stored Procedures?
- What Are Partitioned Tables, Partitions, and Partition Keys?
- How Can I Export the Table Structure?
- How Can I Export All Tables and Views from a Database?
- How Can I Delete Table Data Efficiently?
- How Do I View Foreign Table Information?
- If No Distribution Column Is Specified, How Will Data Be Stored?
- How Do I Replace the Null Result with 0?
- How Do I Check Whether a Table Is Row-Stored or Column-Stored?
- How Do I Query the Information About GaussDB(DWS) Column-Store Tables?
- Why Sometimes the GaussDB(DWS) Query Indexes Become Invalid?
- How Do I Use a User-Defined Function to Rewrite the CRC32() Function?
- What Are the Schemas Starting with pg_toast_temp* or pg_temp*?
- Solutions to Inconsistent GaussDB(DWS) Query Results
- Which System Catalogs That the VACUUM FULL Operation Cannot Be Performed on?
- In Which Scenarios Would a Statement Be "idle in transaction"?
-
Database Performance
- Why Is SQL Execution Slow After Long GaussDB(DWS) Usage?
- Why Does GaussDB(DWS) Perform Worse Than a Single-Server Database in Extreme Scenarios?
- How Can I View SQL Execution Records in a Certain Period When Read and Write Requests Are Blocked?
- What Do I Do If My Cluster Is Unavailable Because of Insufficient Space?
- Snapshot Backup and Restoration
-
General Problems
- Change History
- API Reference (Kuala Lumpur Region)
-
Developer Guide (Kuala Lumpur Region)
- Welcome
- System Overview
-
Data Migration
- Data Migration to GaussDB(DWS)
-
Data Import
- Importing Data from OBS in Parallel
- Using GDS to Import Data from a Remote Server
- Importing Data from MRS to a Cluster
- Importing Data from One GaussDB(DWS) Cluster to Another
- Using the gsql Meta-Command \COPY to Import Data
- Running the COPY FROM STDIN Statement to Import Data
- Full Database Migration
- Metadata Migration
- Data Export
- Other Operations
- Syntax Compatibility Differences Among Oracle, Teradata, and MySQL
- Database Security Management
- Development and Design Proposal
-
Guide: JDBC- or ODBC-Based Development
- Development Specifications
- Downloading Drivers
-
JDBC-Based Development
- JDBC Package and Driver Class
- Development Process
- Loading a Driver
- Connecting to a Database
- Executing SQL Statements
- Processing Data in a Result Set
- Closing the Connection
- Example: Common Operations
- Example: Retrying SQL Queries for Applications
- Example: Importing and Exporting Data Through Local Files
- Example: Migrating Data from MySQL to GaussDB(DWS)
-
JDBC Interface Reference
- java.sql.Connection
- java.sql.CallableStatement
- java.sql.DatabaseMetaData
- java.sql.Driver
- java.sql.PreparedStatement
- java.sql.ResultSet
- java.sql.ResultSetMetaData
- java.sql.Statement
- javax.sql.ConnectionPoolDataSource
- javax.sql.DataSource
- javax.sql.PooledConnection
- javax.naming.Context
- javax.naming.spi.InitialContextFactory
- CopyManager
- ODBC-Based Development
- PostGIS Extension
- Resource Load Management
- Resource Monitoring
-
Query Performance Optimization
- Overview of Query Performance Optimization
- Query Analysis
- Query Improvement
-
Optimization Cases
- Case: Selecting an Appropriate Distribution Column
- Case: Creating an Appropriate Index
- Case: Adding NOT NULL for JOIN Columns
- Case: Pushing Down Sort Operations to DNs
- Case: Configuring cost_param for Better Query Performance
- Case: Adjusting the Distribution Key
- Case: Adjusting the Partial Clustering Key
- Case: Adjusting the Table Storage Mode in a Medium Table
- Case: Adjusting the Local Clustering Column
- Case: Reconstructing Partition Tables
- Case: Adjusting the GUC Parameter best_agg_plan
- Case: Rewriting SQL and Deleting Subqueries (Case 1)
- Case: Rewriting SQL and Deleting Subqueries (Case 2)
- Case: Rewriting SQL Statements and Eliminating Prune Interference
- Case: Rewriting SQL Statements and Deleting in-clause
- Case: Setting Partial Cluster Keys
- SQL Execution Troubleshooting
- Common Performance Parameter Optimization Design
- User-Defined Functions
- Stored Procedures
-
System Catalogs and System Views
- Overview of System Catalogs and System Views
-
System Catalogs
- GS_OBSSCANINFO
- GS_WLM_INSTANCE_HISTORY
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Copied.
CREATE FOREIGN TABLE (for GDS Import and Export)
CREATE FOREIGN TABLE creates a GDS foreign table.
Function
CREATE FOREIGN TABLE creates a GDS foreign table in the current database for concurrent data import and export. The GDS foreign table can be read-only or write-only, used for concurrent data import and export, respectively. The OBS foreign table is read-only by default.
Precautions
- The foreign table is owned by the user who runs the command.
- The distribution mode of a GDS foreign table does not need to be explicitly specified. The default is ROUNDROBIN.
- All constraints (including column and row constraints) are invalid to the GDS foreign table.
Syntax
1 2 3 4 5 6 7 8 9 |
CREATE FOREIGN TABLE [ IF NOT EXISTS ] table_name ( [ { column_name type_name POSITION(offset,length) | LIKE source_table } [, ...] ] ) SERVER gsmpp_server OPTIONS ( { option_name ' value ' } [, ...] ) [ { WRITE ONLY | READ ONLY }] [ WITH error_table_name | LOG INTO error_table_name] [REMOTE LOG 'name'] [PER NODE REJECT LIMIT 'value'] [ TO { GROUP groupname | NODE ( nodename [, ... ] ) } ]; |
Parameter Overview
CREATE FOREIGN TABLE provides multiple parameters, which are classified as follows:
- Mandatory parameters
- Optional parameters
- Data source location parameter for foreign tables: location
- Data format parameters
- format
- header (only for CSV and FIXED source data files)
- fileheader (only for CSV and FIXED source data files)
- out_filename_prefix
- delimiter
- quote (only for CSV source data files)
- escape (only for CSV source data files)
- null
- noescaping (only for TEXT source data files)
- encoding
- eol
- conflict_delimiter
- file_type
- auto_create_pipe
- Error-tolerance parameters
- Performance parameter
Parameter Description
- IF NOT EXISTS
Does not throw an error if a table with the same name already exists. A notice is issued in this case.
- table_name
Specifies the name of the foreign table to be created.
Value range: a string. It must comply with the naming convention.
- column_name
Specifies the name of a column in the foreign table.
Value range: a string. It must comply with the naming convention.
- type_name
Specifies the data type of the column.
- POSITION(offset,length)
Defining the location of each column in the data file in fixed length mode.
NOTE:
offset is the start of the column in the source file, and length is the length of the column.
Value range: offset must be greater than 0 bytes, and its unit is byte.
The length of each record must be less than 1 GB. By default, columns not in the file are replaced with null.
- SERVER gsmpp_server
Specifies the server name of the foreign table. For the GDS foreign table, its server is created by initial database, which is gsmpp_server.
- OPTIONS ( { option_name ' value ' } [, ...] )
Specifies all types of parameters of foreign table data.
- location
Specifies the data source location of the foreign table, which can be expressed through URLs. Separate URLs with vertical bars (|).
Currently, GDS can automatically create a directory defined by a foreign table during data export. For example, when the foreign table location defines that gsfs:// 192.168.0.91:5000/2019/09 executes an export task, if the 2019/09 subdirectory in the GDS data directory does not exist, the subdirectory is automatically created. You do not need to manually create the directory specified in the foreign table.
NOTE:
- For a read-only foreign table imported by GDS from a remote server in parallel, its URL must end with its corresponding schema or file name. (Read-only is the default file attribute.)
For example: gsfs://192.168.0.90:5000/* or file:///data/data.txt or gsfs:// 192.168.0.90:5000/* | gsfs:// 192.168.0.91:5000/*.
- For a writable foreign table used for GDS to export data to a remote server in parallel, file names are not required in URLs. If the data source location is a remote URL, for example, gsfs:// 192.168.0.90:5000/, multiple data sources can be specified. If the number of exported data file locations is less than or equal to the number of DNs, when you use the foreign table for export, data is evenly distributed to each data source location. If the number of exported data file locations is greater than the number of DNs, when you export data, the data is evenly distributed to data source locations corresponding to the DNs. Blank data files are created on the excess data source locations.
- For a foreign table used for GDS to import data from a remote server in parallel, the number of URLs must be less than the number of DNs, and URLs containing the same location cannot be used.
- If the URL begins with gsfss://, data is imported and exported in encryption mode, and DOP cannot exceed 10.
- During GDS export, the 2019/09 subdirectory in THE gsfs://127.0.0.1:7789/2019/09/ directory specified by the location table is automatically created when the export task is executed.
- If file_type is set to pipe, GDS determines whether the target file to be imported or exported is a pipe file or a directory based on whether the last character in the URL is a slash (/). Example:
- In gsfs://192.168.0.90:5000/a/b, GDS identifies b as a pipe file.
- In gsfs://192.168.0.90:5000/a/b/, GDS identifies b as a directory and creates a pipe file in the directory.
- For a read-only foreign table imported by GDS from a remote server in parallel, its URL must end with its corresponding schema or file name. (Read-only is the default file attribute.)
- format
Specifies the format of the data source file in a foreign table.
Value range: CSV, TEXT. The default value is TEXT.
- In CSV files, escape sequences are processed as common strings. Therefore, linefeeds are processed as data.
- In TEXT files, escape sequences are processed as they are. Therefore, linefeeds are not processed as data.
NOTE:
- An escape sequence is a string starting with a backslash (\), including \b (backspace), \f (formfeed page break), \n (new line), \r (carriage return), \t (horizontal tab), \v (vertical tab), \number (octal number), and \xnumber (hexadecimal number). In TEXT files, strings are processed as they are. In files of other formats, strings are processed as data.
- header
Specifies whether a data file contains a table header. header is available only for CSV and FIXED files.
When data is imported, if header is on, the first row of the data file will be identified as title row and ignored. If header is off, the first row is identified as data.
When data is exported, if header is on, fileheader must be specified. fileheader is used to specify the export header file format. If header is off, the exported file does not include a title row.
Value range: true, on, false, and off. The default value is false or off.
- fileheader
Specifies a file that defines the content in the header for exported data. The file contains one row of data description of each column.
For example, to add a header in a file containing product information, define the file as follows:
The information of products.\n
NOTICE:
- This parameter is available only when header is on or true. The file must be prepared in advance.
- In Remote mode, the definition file must be put to the working directory of GDS (the -d directory specified when starting the GDS).
- The definition file can contain only one row of title information, and end with a newline character. Excess rows will be discarded. (Title information cannot contain newline character).
- The length of the definition file including the newline character cannot exceed 1 MB.
- out_filename_prefix
Specifies the name prefix of the exported data file exported using GDS from a write-only foreign table.
If file_type is set to pipe, the pipe file dbName_schemaName_foreignTableName.pipe is generated.
If both out_filename_prefix and location specify a pipe name, the pipe name specified in location is used.
NOTICE:
- The prefix of the specified file name must be valid and compliant with the restrictions of the file system in the physical environment where the GDS is deployed. Otherwise, the file will fail to be created.
- The file name prefix can contain only lowercase letters, uppercase letters, digits, and underscores (_).
- The prefix of the specified export file name cannot contain feature fields reserved for the Windows and Linux OS, including but not limited to:
"con","aux","nul","prn","com0","com1","com2","com3","com4","com5","com6","com7","com8","com9","lpt0","lpt1","lpt2","lpt3","lpt4","lpt5","lpt6","lpt7","lpt8","lpt9"
- The total length of the absolute path consisting of the exported file prefix, the path specified by GDS –d, .dat, or .pipe should be as required by the file system where GDS is deployed.
- It is required that the prefix can be correctly parsed and identified by the receiver (including but not limited to the original database where it was exported) of the data file. Identify and modify the option that causes the file name resolution problem (if any).
- To concurrently perform export jobs, do not use the same file name prefix for them. Otherwise, the exported files may overwrite each other or be lost in the OS or file system.
- The prefix of the specified file name must be valid and compliant with the restrictions of the file system in the physical environment where the GDS is deployed. Otherwise, the file will fail to be created.
- delimiter
Specifies the column delimiter of data, and uses the default delimiter if it is not set. The default delimiter of TEXT is a tab and that of CSV is a comma (,). No delimiter is used in FIXED format.
NOTE:
- A delimiter cannot be \r or \n.
- A delimiter cannot be the same as the null value. The delimiter of CSV cannot be same as the quote value.
- The delimiter for the TEXT format data cannot contain any of the following characters: \.abcdefghijklmnopqrstuvwxyz0123456789.
- The data length of a single row should be less than 1 GB. If the delimiters are too long and there are too many rows, the length of valid data will be affected.
- You are advised to use a multi-character, such as the combination of the dollar sign ($), caret (^), the ampersand (&), or invisible characters, such as 0x07, 0x08, and 0x1b as the delimiter.
- For a multi-character delimiter, do not use the same characters, for example, ---.
Valid value:
The value of delimiter can be a multi-character delimiter whose length is less than or equal to 10 bytes.
- quote
Specifies which characters in a CSV source data file will be identified as quotation marks. The default value is a double quotation mark (").
NOTE:
- The quote parameter cannot be the same as the delimiter or null parameter.
- The quote parameter must be a single-byte character.
- Invisible characters are recommended as quote values, such as 0x07, 0x08, and 0x1b.
- escape
Specifies which characters in a CSV source data file are escape characters. Escape characters can only be single-byte characters.
Default value: the same as the value of QUOTE
- null
Specifies the string that represents a null value.
NOTE:
- The null value cannot be \r or \n. The maximum length is 100 characters.
- The null value cannot be the same as the delimiter or quote parameter.
Valid value:
- The default value is \n for the TEXT format.
- The default value for the CSV format is an empty string without quotation marks.
- noescaping
Specifies in TEXT format, whether to escape the backslash (\) and its following characters.
NOTE:
noescaping is available only for the TEXT format.
Value range: true, on, false, and off. The default value is false or off.
- encoding
Specifies the encoding of a data file, that is, the encoding used to parse, check, and generate a data file. Its default value is the default client_encoding value of the current database.
Before you import foreign tables, it is recommended that you set client_encoding to the file encoding format, or a format matching the character set of the file. Otherwise, unnecessary parsing and check errors may occur, leading to import errors, rollback, or even invalid data import. Before you import foreign tables, you are also advised to specify this parameter, because the export result using the default character set may not be what you expected.
If this parameter is not specified when you create a foreign table, a warning message will be displayed on the client.
NOTE:
Currently, GDS cannot parse or write in a file using multiple encoding formats during foreign table import or export.
- fill_missing_fields
Specifies whether to generate an error message when the last column in a row in the source file is lost during data import.
Value range: true, on, false, and off. The default value is false or off.
- If this parameter is set to true or on and the last column of a data row in a data source file is lost, the column will be replaced with NULL and no error message will be generated.
- If this parameter is set to false or off and the last column is missing, the following error information will be displayed:
missing data for column "tt"
- ignore_extra_data
Specifies whether to ignore excessive columns when the number of data source files exceeds the number of foreign table columns. This parameter is available during data import.
Value range: true, on, false, and off. The default value is false or off.
- If this parameter is set to true or on and the number of data source files exceeds the number of foreign table columns, excessive columns will be ignored.
- If this parameter is set to false or off and the number of data source files exceeds the number of foreign table columns, the following error information will be displayed:
extra data after last expected column
NOTICE:
If the newline character at the end of the row is lost, setting the parameter to true will ignore data in the next row.
- reject_limit
Specifies the maximum number of data format errors allowed during a data import task. If the number of errors does not reach the maximum number, the data import task can still be executed.
NOTICE:
You are advised to replace this syntax with PER NODE REJECT LIMIT 'value'.
Examples of data format errors include the following: a column is lost, an extra column exists, a data type is incorrect, and encoding is incorrect. Once a non-data format error occurs, the whole data import process is stopped.
Value range: a positive integer or unlimited
The default value is 0, indicating that error information is returned immediately.
NOTE:
Enclose positive integer values with single quotation marks ('').
- mode
Specifies the data import policy during a specific data import process. GaussDB(DWS) supports only the Normal mode.
Valid value:
- Normal (default): supports all file types (CSV, TEXT, FIXED). Enabling Gauss data service to help data import.
- eol
Specifies the newline character style of the imported or exported data file.
Value range: multi-character newline characters within 10 bytes. Common newline characters include \r (0x0D), \n (0x0A), and \r\n (0x0D0A). Special newline characters include $ and #.
NOTE:
- The eol parameter supports only the TEXT format for data import and export and does not support the CSV or FIXED format for data import. For forward compatibility, the eol parameter can be set to 0x0D or 0x0D0A for data export in the CSV and FIXED formats.
- The value of the eol parameter cannot be the same as that of DELIMITER or NULL.
- The eol parameter value cannot contain lowercase letters, digits, or dot (.).
- conflict_delimiter
This parameter is generally used with the compatible_illegal_chars parameter. If a data file contains a truncated Chinese character, the truncated character and a delimiter will be encoded into another Chinese character due to inconsistent encoding between the foreign table and the database. As a result, the delimiter is masked and an error will be reported, indicating that there are missing fields.
This parameter is used to avoid encoding a truncated character and a delimiter into another character.
Value range: true, on, false, and off. The default value is false or off.
- If the parameter is set to true or on, encoding a truncated character and a delimiter into another character is allowed.
- If the parameter is set to false or off, encoding a truncated character and a delimiter into another character is not allowed.
NOTICE:
This parameter is disabled by default. It is recommended that you disable this parameter, because encoding a truncated character and a delimiter into another character is rarely required. If the parameter is enabled, the scenario may be incorrectly identified and thereby causing incorrect information imported to the table.
- file_type
Specifies the type of the file to be imported or exported.
Value options: normal, pipe. normal is the default value.
- If this parameter is set to normal, the file to be imported or exported is a common file.
- If this parameter is set to pipe, the file to be imported or exported is a named pipe.
- auto_create_pipe
This parameter specifies whether the GDS process automatically creates a named pipe.
Value options: true, on, false, and off. The default value is true/on.
- If this parameter is set to true or on, the GDS process is allowed to automatically create a named pipe.
- If this parameter is set to false or off, you need to manually create a named pipe.
NOTICE:
- When setting auto_create_pipe, set file_type to pipe. Otherwise, the foreign table cannot be created.
- If auto_create_pipe is set to false and no pipe is specified during data import and export, the database name_schema name_foreign table name.pipe file will be opened. If a pipe has been specified, the specified pipe in the location will be opened. If the named pipe is not written by other programs or is not opened in write mode within the period specified by the pipe-timeout parameter, an error message is displayed indicating that the import or export task times out. If the file is not a pipe, an error is reported when the import or export task is executed.
- If auto_create_pipe is set to true and no pipe file is specified during data import and export, the database name_schema name_foreign table name.pipe file will be opened. If the file is a common file, an error is reported when the file is imported or exported. If the file is a pipe, the system automatically deletes the file and re-creates the named pipe.
- You can use the location parameter to specify the pipe when exporting data, for example, location'gsfs://127.0.0.1:7789/aa.pipe. When auto_create_pipe is set to true, GDS automatically creates the aa.pipe file in the data directory.
- fix
Specifies the length of fixed format data. The unit is byte. This syntax is available only for READ ONLY foreign tables.
Value range: Less than 1 GB, and greater than or equal to the total length specified by POSITION (The total length is the sum of offset and length in the last column of the table definition.)
- out_fix_alignment
Specifies how the columns of the types BYTEAOID, CHAROID, NAMEOID, TEXTOID, BPCHAROID, VARCHAROID, NVARCHAR2OID, and CSTRINGOID are aligned during fixed-length export.
Value range: align_left, align_right
Default value: align_right
NOTICE:
The bytea data type must be in hexadecimal format (for example, \XXXX) or octal format (for example, \XXX\XXX\XXX). The data to be imported must be left-aligned (that is, the column data starts with either of the two formats instead of spaces). Therefore, if the exported file needs to be imported using a GDS foreign table and the file data length is less than that specified by the foreign table formatter, the exported file must be left aligned. Otherwise, an error is reported during the import.
- date_format
Imports data of the DATE type. This syntax is available only for READ ONLY foreign tables.
Value range: any valid DATE value. For details, see Date and Time Processing Functions and Operators.
NOTE:
If ORACLE is specified as the compatible database, the DATE format is TIMESTAMP. For details, see timestamp_format below.
- time_format
Imports data of the TIME type. This syntax is available only for READ ONLY foreign tables.
Value range: any valid TIME value. Time zones cannot be used. For details, see Date and Time Processing Functions and Operators.
- timestamp_format
Imports data of the TIMESTAMP type. This syntax is available only for READ ONLY foreign tables.
Value range: any valid TIMESTAMP value. Time zones are not supported. For details, see Date and Time Processing Functions and Operators.
- smalldatetime_format
Imports data of the SMALLDATETIME type. This syntax is available only for READ ONLY foreign tables.
Value range: any valid SMALLDATETIME value. For details, see Date and Time Processing Functions and Operators.
- compatible_illegal_chars
Enables or disables fault tolerance on invalid characters during data import. This syntax is available only for READ ONLY foreign tables.
Value range: true, on, false, and off. The default value is false or off.
- If this parameter is set to true or on, invalid characters are tolerated and imported to the database after conversion.
- If this parameter is set to false or off and an error occurs when there are invalid characters, the import will be interrupted.
NOTE:
The rule of error tolerance when you import invalid characters is as follows:
(1) \0 is converted to a space.
(2) Other invalid characters are converted to question marks.
(3) If compatible_illegal_chars is set to true or on, invalid characters are tolerated. If NULL, DELIMITER, QUOTE, and ESCAPE are set to a spaces or question marks. Errors like "illegal chars conversion may confuse COPY escape 0x20" will be displayed to prompt user to modify parameter values that cause confusion, preventing import errors.
- location
- READ ONLY
Specifies whether a foreign table is read-only. This parameter is available only for data import.
- WRITE ONLY
Specifies whether a foreign table is write-only. This parameter is available only for data import.
- WITH error_table_name
Specifies the table where data format errors generated during parallel data import are recorded. You can query the error information table after data is imported to obtain error details. This parameter is available only after reject_limit is set.
NOTE:
To be compatible with PostgreSQL open source interfaces, you are advised to replace this syntax with LOG INTO.
Value range: a string. It must comply with the naming convention.
- LOG INTO error_table_name
Specifies the table where data format errors generated during parallel data import are recorded. You can query the error information table after data is imported to obtain error details.
NOTE:
This parameter is available only after PER NODE REJECT LIMIT is set.
Value range: a string. It must comply with the naming convention.
- file_sequence
Concurrently imports data in parallel through GDS foreign tables, to improve single-file import performance. This parameter is only used for data import.
The parameter format is file_sequence'total number of shards-current shard'. Example:
file_sequence '3-1' indicates that the imported file is logically split into three shards and the data currently imported by the foreign table is the data on the first shard.
file_sequence '3-2' indicates that the imported file is logically split into three shards and the data currently imported by the foreign table is the data on the second shard.
file_sequence '3-3' indicates that the imported file is logically split into three shards and the data currently imported by the foreign table is the data on the third shard.
This parameter has the following constraints:
- A file can be split to a maximum of 8 shards.
- The number of currently imported shard should be less than or equal to the total number of split shards.
- Only CSV and TXT files can be imported.
NOTE:
When data is imported in parallel in CSV format, some shards fail to be imported in the following scenario because the CSV rules conflict with the GDS splitting logic:
Scenario: A CSV file contains a newline character that is not escaped, the newline character is contained in the character specified by quote, and the data of this line is in the first row of the logical shard.
For example, if you import the big.csv file in parallel, the following information is displayed:
--id, username, address 10001,"customer1 name","Rose District" 10002,"customer2 name"," 23 Road Rose District NewCity" 10003,"customer3 name","NewCity"
After the file is split into two shards, the content of the first shard is as follows:
10001,"customer1 name","Rose District" 10002,"customer2 name"," 23
The content of the second shard is as follows:
Road Rose District NewCity" 10003,"customer3 name","NewCity"
The newline character after 23 Road Rose in the first line of the second shard is contained between double quotation marks. As a result, GDS cannot determine whether the newline character is a newline character in the field or a separator in the line. Therefore, two data records on the first shard are successfully imported, but the second shard fails to be imported.
- REMOTE LOG 'name'
The data format error information is saved as files in GDS. name is the prefix of the error data file.
- PER NODE REJECT LIMIT 'value'
This parameter specifies the allowed number of data format errors on each DN during data import. If the number of errors exceeds the specified value on any DN, data import fails, an error is reported, and the system exits data import.
NOTICE:
This syntax specifies the error tolerance of a single node.
Examples of data format errors include the following: a column is lost, an extra column exists, a data type is incorrect, and encoding is incorrect. When a non-data format error occurs, the whole data import process stops.
Value range: integer, unlimited. The default value is 0, indicating that error information is returned immediately.
- TO { GROUP groupname | NODE ( nodename [, ... ] ) }
Currently, TO GROUP cannot be used. TO NODE is used for internal scale-out tools.
Examples
Create a foreign tablecustomer_ft to import data from GDS server 10.10.123.234 in TEXT format.
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CREATE FOREIGN TABLE customer_ft ( c_customer_sk integer , c_customer_id char(16) , c_current_cdemo_sk integer , c_current_hdemo_sk integer , c_current_addr_sk integer , c_first_shipto_date_sk integer , c_first_sales_date_sk integer , c_salutation char(10) , c_first_name char(20) , c_last_name char(30) , c_preferred_cust_flag char(1) , c_birth_day integer , c_birth_month integer , c_birth_year integer , c_birth_country varchar(20) , c_login char(13) , c_email_address char(50) , c_last_review_date char(10) ) SERVER gsmpp_server OPTIONS ( location 'gsfs://10.10.123.234:5000/customer1*.dat', FORMAT 'TEXT' , DELIMITER '|', encoding 'utf8', mode 'Normal') READ ONLY; |
Create a foreign table to import data from GDS servers 192.168.0.90 and 192.168.0.91 in TEXT format. Record errors that occur during data import in foreign_HR_staffS_ft. A maximum of two data format errors are allowed during the data import.
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CREATE FOREIGN TABLE foreign_HR_staffS_ft ( staff_ID NUMBER(6) , FIRST_NAME VARCHAR2(20), LAST_NAME VARCHAR2(25), EMAIL VARCHAR2(25), PHONE_NUMBER VARCHAR2(20), HIRE_DATE DATE, employment_ID VARCHAR2(10), SALARY NUMBER(8,2), COMMISSION_PCT NUMBER(2,2), MANAGER_ID NUMBER(6), section_ID NUMBER(4) ) SERVER gsmpp_server OPTIONS (location 'gsfs://192.168.0.90:5000/* | gsfs://192.168.0.91:5000/*', format 'TEXT', delimiter E'\x08', null '',reject_limit '2') WITH err_HR_staffS_ft; |
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