Glossary_GaussDB(DWS)

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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
- Getting Started with Common Practices
User Guide
- Using GaussDB(DWS)
- Preparations
- Creating a GaussDB(DWS) Cluster
- Connecting to a GaussDB(DWS) Cluster
- Creating a GaussDB(DWS) Database and User
- Migrating Service Data to a GaussDB(DWS) Cluster
  - Migrating Data to a GaussDB(DWS) Cluster Using GDS-Kafka
  - Data Source Management
- GaussDB(DWS) Cluster Data Security and Encryption
- GaussDB(DWS) Cluster Management
- GaussDB(DWS) Cluster O&M
Best Practices
- Import and Export
- Data Migration
- Data Analytics
- Decoupled Storage and Compute
  - DWS 3.0 Decoupled Storage and Compute Usage Suggestions and Performance Optimization
- Data Development
- Database Management
- Performance Tuning
  - Optimizing Table Structure Design to Enhance GaussDB(DWS) Query Performance
  - Analyzing SQL Statements That Are Being Executed to Handle GaussDB(DWS) Performance Issues
- Cluster Management
  - Binding Different Resource Pools to Two Types of Jobs to Balance Load for GaussDB(DWS)
  - Scaling Options for GaussDB(DWS) with a Coupled Storage-Compute Architecture
Data Migration and Synchronization
- Data Migration to GaussDB(DWS)
- Importing Data
- Full Database Migration
  - Using CDM to Migrate Data to GaussDB(DWS)
  - Using DSC to Migrate SQL Scripts
- Real-time Import
  - Using DRS to Import Data to GaussDB(DWS)
  - Real-time Data Import From Kafka GaussDB(DWS)
- Metadata Migration
  - Using gs_dump and gs_dumpall to Export Metadata
  - Using gs_restore to Import Data
- Exporting Data
- Other Operations
Developer Guide
- Standard data warehouse (9.1.0.x)
- Standard data warehouse (8.1.3.x)
- Hybrid Data Warehouse (9.1.0.x）
- Hybrid Data Warehouse (8.1.3.x）
- Historical Versions
SQL Syntax Reference
- SQL Syntax Reference (9.1.0.x)
- SQL Syntax Reference (8.1.3.x)
- Historical Versions
Performance Tuning
- Overview of Query Performance Optimization
- Query Execution Process
- SQL Execution Plan
- SQL Optimization Guide
- Optimization Cases
- SQL Execution Troubleshooting
- query_band Load Identification
- Common Performance Parameter Optimization Design
Tool Guide
- Overview
- Downloading Related Tools
- gsql
- Data Studio
- GDS
- DSC
- DataCheck
- DWS-Connector
- Server Tool
API Reference
- Before You Start
- API Overview
- Calling APIs
- Getting Started
- API Description
- Application Cases
  - Using Postman to Call the API for Creating a Cluster
  - Using Postman to Call the API for Creating a Snapshot
- Introduction
- Appendix
SDK Reference
- SDK Overview
FAQs
- Top FAQs
- Product Consulting
- Database Connections
- Data Migration
- Database Usage
- Cluster Management
- Account Permissions
- Database Performance
- Backup and Restoration
  1. Why Does It Take a Long Time to Create an Automated Snapshot in GaussDB(DWS)?
  2. Does a GaussDB(DWS) Snapshot Have the Same Function as an EVS Snapshot?
Troubleshooting
- Database Connections
- JDBC/ODBC
- Data Import and Export
- Database Parameter Modification
- Account/Permission/Password
- Cluster Performance
- Cluster Exceptions
  - The Disk Usage Alarm Is Frequently Generated
- Database Use
Videos
Performance White Paper
- Overview
- Test Result
  - TPC-H Single Query Test
  - TPC-DS Single Query Test
- Test Methods
- Appendixes
  - TPC-H Test Sets
  - TPC-DS Test Sets
Technical White Paper
- GaussDB(DWS)
- Platforms and Technical Specifications Supported by GaussDB(DWS)
  - Technical Specifications
- GaussDB(DWS) Core Technologies
- GaussDB(DWS) Tools
  - Client Tools
  - Database Monitoring Tool
- External APIs
Error Code Reference
- 8.2.0 and earlier versions
  - Management Console Error Code
  - Data Warehouse Service Error Codes
- 8.2.1 or later versions
Glossary
More Documents
- User Guide
- API Reference (ME-Abu Dhabi Region)
- Developer Guide (ME-Abu Dhabi Region)
- SQL Syntax Reference (ME-Abu Dhabi Region)
- Tool Guide (ME-Abu Dhabi Region)
- Error Code Reference (ME-Abu Dhabi Region)
  - Management Console Error Code
- User Guide (Paris Region)
- API Reference (Paris Region)
- Developer Guide (Paris Region)
- SQL Syntax Reference (Paris Region)
- Tool Guide (Paris Region)
- Error Code Reference (Paris Region)
  - Management Console Error Code
- User Guide (Kuala Lumpur Region)
- API Reference (Kuala Lumpur Region)
- Developer Guide (Kuala Lumpur Region)
- SQL Syntax Reference (Kuala Lumpur Region)
- Tool Guide (Kuala Lumpur Region)
- Error Code Reference (Kuala Lumpur Region)
  - Management Console Error Code
General Reference
- Glossary
- Service Level Agreement
- White Papers
- Endpoints
- Permissions

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Help Center/ GaussDB(DWS)/ Glossary

A-E

A

advanced package

Logical and functional stored procedures and functions provided by the database.
C

checkpoint

A mechanism that stores data from the database memory to disks at a certain time. The database periodically stores the data of committed transactions and data of uncommitted transactions to disks. The data and redo logs can be used for database restoration if a database restarts or breaks down.

cluster

The smallest management unit in DWS. A cluster represents a separately running data warehouse. Users can manage the lifecycle of a cluster in DWS.

column

An equivalent concept of field. A database table consists of one or more columns.

Compression Unit

Compression Unit (CU) is the smallest storage unit in a column-storage table.

concurrency control

A DBMS service that ensures data integrity when multiple transactions are concurrently executed in a multi-user environment. In a multi-threaded DWS environment, concurrency control ensures that database operations are safe and all database transactions remain consistent at any given time.

CU

See Compression Unit
D

data control language

A subset of SQL for setting or modifying database user or role rights.

data definition language

A subset of SQL for defining data structures and database objects.

data dictionary

A reserved table within a database which is used to store information about the database itself. The information includes database design information, stored procedure information, user rights, user statistics, database process information, database increase statistics, and database performance statistics.

data manipulation language

A subset of SQL for accessing data for database objects.

data partitioning

The action of dividing a table into parts (partitions) whose data does not overlap within a database instance. Tables can be partitioned by range, where the target storage location is mapped based on the range of the values in the column that is specified in the tuple.

Data Warehouse Service

Data Warehouse Service is an online data processing database based on the public cloud infrastructure and platform and helps you mine and analyze massive sets of data.

database

A collection of data that is stored together and can be accessed, managed, and updated. Data in a view in the database can be classified into the following types: numerals, full text, digits, and images.

database instance

A process and the database files that it controls. The cluster installs multiple database instances on one physical node. The GTM, CM, CN, and DN installed on cluster nodes are all database instances. A database instance is also called a logical node.

DCL

See data control language

DDL

See data definition language

Degraded

The cluster goes into the state when some nodes in the cluster are faulty and cannot work properly, but the whole cluster runs properly.

DML

See data manipulation language

DWS

See Data Warehouse Service
E

ETL

See Extract-Transform-Load

Extract-Transform-Load

A process of data transmission from the source to the target database.

F-J

G

GDS

See General Data Service

General Data Service

General Data Service (GDS) is a parallel data loading tool. When importing data to DWS, users need to deploy the tool on the server where the source data is stored so that DataNodes can use this tool to obtain data.
I

index

An ordered data structure in the database management system. An index accelerates querying and updating of data in database tables.

Internet of Things

The Internet of things is the network of physical devices, vehicles, home appliances and other items embedded with electronics, software, sensors, actuators, and network connectivity which enables these objects to connect and exchange data.

IoT

See Internet of Things

K-O

L

low performance

A situation where some nodes in a cluster become unavailable, which affects the cluster performance
M

massively parallel processing

Massively parallel processing (MPP) refers to cluster architecture that consists of multiple machines. The architecture is also called a cluster system.

metadata

Data that provides information about other data. Metadata describes the source, size, format, or other characteristics of data. In the data field, metadata helps to explain the content of a data warehouse.

MPP

See massively parallel processing
N

node

A basic metering unit in DWS. It includes user-specified computing and storage resources and virtual machines (VMs) where DWS programs are deployed.
O

O2O

See Online to Offline

OLAP

See Online Analytical Processing

Online Analytical Processing

A technology that uses multidimensional structures to provide rapid data access for analysis. OLAP source data is generally stored in data warehouses in a relational database.

Online to Offline

Online to offline, or O2O, refers to a marketing mode that uses online marketing and purchase to drive offline operation and consumption. O2O pushes offline stores' messages and promotions to Internet users by providing discounts and service reservations to convert Internet users to offline customers. This is especially suitable for products and services that must be consumed in offline stores, for example, catering, fitness, movies and performances, beauty salon. In 2013, the O2P marketing mode appeared, that is, the localized O2O marketing mode, formally bringing O2O into the localization process.

P-T

P

Page

Minimum memory unit for row storage in the relationship object structure. The default size of a page is 8 KB.
Q

query operator

An iterator or a query tree node, which is a basic unit for the execution of a query. Execution of a query can be split into one or more query operators. Common query operators include scan, join, and aggregation.
R

read-only

When a data warehouse enters read-only state, it responds only to reads. The warehouse becomes read-only in many situations, for example, when you create a cluster snapshot or when 90% of the cluster's storage capacity is used.

Redistributing

The cluster goes into the state when it detects that the service data volume on some nodes is signifi-cantly larger than that on other nodes. In this case, the cluster automatically redistributes data on all nodes.

Redistribution-failure

The cluster goes into the state when data redistribu-tion fails, but no data loss occurs.

redo log

A log that records operations on the database. Redo logs contain the information required for performing these operations again. If a database is faulty, redo logs can be used to restore the database to its pre-fault state.
S

schema

A database object set that includes the logical structure, such as tables, views, sequences, stored procedures, synonyms, indexes, clusters, and database links.

segment

A segment in the database indicates a part containing one or more regions. Region is the smallest range of a database and consists of data blocks. One or more segments comprise a tablespace.

shared-nothing architecture

A distributed computing architecture, in which none of the nodes share a CPU or storage resources. This architecture has good scalability.

snapshot

A full backup of a cluster. Snapshots are stored in the storage space of Object Storage Service (OBS).

snapshot restoration

A snapshot can be used to restore a cluster to a newly created one that has the same specifications. Currently, you can restore a cluster only to a new one.

SQL

See Structure Query Language

statistics

Information that is automatically collected by databases, including table-level information (number of tuples and number of pages) and column-level information (distribution histograms of value ranges of columns). Statistics in databases are used to estimate the cost of query plans to find the plan with the lowest cost.

stored procedure

A group of SQL statements compiled to perform certain functions and stored in a large database system. Users can specify a name and parameters (if any) for a stored procedure to execute the procedure.

Structure Query Language

Structure Query Language (SQL) is a standard database query language. It consists of DDL, DML, and DCL.

system table

A table storing meta information about the database. The meta information includes user tables, indexes, columns, functions, and data types in a database.
T

table

A set of columns and rows. The value in each column represents data of a certain type. For example, if a table contains people's names, cities, and states, it has three columns: Name, City, and State. In every row in the table, the Name column contains a name, the City column contains a city, and the State column contains a state.

tablespace

A tablespace is a logical storage structure that contains tables, indexes, large objects, and long data. A tablespace provides an abstract layer between physical data and logical data, and provides storage space for all database objects. When you create a table, you can specify which tablespace it belongs to.

TPC Benchmark DS

The TPC Benchmark DS (TPC-DS) is a decision support benchmark provided by the Transaction Processing Performance Council (TPC) that models several generally applicable aspects of a decision support system, including queries and data maintenance. The benchmark provides a representative evaluation of performance as a general purpose decision support system. For more information about the benchmark, visit http://www.tpc.org/tpcds/.

TPC-DS

See TPC Benchmark DS

transaction

A logical unit of work performed within a database management system against a database. A transaction consists of a limited database operation sequence, and must have ACID features.

U-Z

U-Z

WAL

See Write-ahead logging

Write-ahead logging

Write-ahead logging (WAL) is a standard method for logging a transaction. Corresponding logs must be written into a permanent device before a data file (carrier for a table and index) is modified.

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A-E

advanced package

checkpoint

cluster

column

Compression Unit

concurrency control

CU

data control language

data definition language

data dictionary

data manipulation language

data partitioning

Data Warehouse Service

database

database instance

DCL

DDL

Degraded

DML

DWS

ETL

Extract-Transform-Load

F-J

GDS

General Data Service

index

Internet of Things

IoT

K-O

low performance

massively parallel processing

metadata

MPP

node

O2O

OLAP

Online Analytical Processing

Online to Offline

P-T

Page

query operator

read-only

Redistributing

Redistribution-failure

redo log

schema

segment

shared-nothing architecture

snapshot

snapshot restoration

SQL

statistics

stored procedure

Structure Query Language

system table

table

tablespace

TPC Benchmark DS

TPC-DS

transaction

U-Z

WAL

Write-ahead logging

Feedback

Was this page helpful?

Feedback