- What's New
- Product Bulletin
- Service Overview
- Billing
- Getting Started
-
User Guide
- Function Overview
- Kernel Version Notes
- Permissions Management
-
Instance Management
- Instance Statuses
- Buying a DDM instance
- Splitting Read-only and Read-Write Services
- Changing Node Class
- Scaling Out a DDM Instance
- Scaling In a DDM Instance
- Restarting a DDM Instance or an Instance Node
- Deleting Pay-per-Use Instances
- Reloading Table Data
- Changing a Parameter Template
- Modifying Parameters of a DDM Instance
- Rolling Back the Version of a DDM Instance
- Upgrading the Version of a DDM Instance
- Upgrading the DDM Engine and OS
- Connection Management
- Schema Management
- Shard Configuration
- Data Nodes
-
Parameter Template Management
- Instance Parameters
- Creating a Parameter Template
- Modifying a Custom Parameter Template
- Comparing Two Parameter Templates
- Viewing Parameter Change History
- Replicating a Parameter Template
- Applying a Parameter Template
- Viewing Application Records of a Parameter Template
- Modifying the Description of a Parameter Template
- Deleting a Parameter Template
- Account Management
- Backups and Restorations
-
Data Migration
- Overview
- Migration Evaluation
- Scenario 1: Migrating Data from an On-Premises MySQL Instance to DDM
- Scenario 2: Migrating Data from a Third-Party Cloud MySQL Instance to DDM
- Scenario 3: Migrating Data from an ECS-hosted MySQL Instance on Huawei Cloud to DDM
- Scenario 4: Exporting Data from a DDM Instance
- Scenario 5: Migrating Data from Heterogeneous Databases to DDM
- Scenario 6: Migrating Data from Huawei Cloud RDS for MySQL to DDM
- Session Management
- Slow Queries
- Monitoring and Alarm Reporting
- Task Center
- Tags
- Auditing
-
SQL Syntax
- Introduction
- DDL
- DML
- Online DDL
- Functions
- Unsupported Objects and Use Constraints
- Supported SQL Statements
- Global Sequence
- Database Management Syntax
- Advanced SQL Functions
- Quotas
-
API Reference
- Before You Start
- API Overview
- Calling APIs
-
APIs (Recommended)
-
DDM Instances
- Buying a DDM instance
- Querying DDM Instances
- Querying Details of a DDM Instance
- Modifying the Name of a DDM Instance
- Changing the Security Group of a DDM Instance
- Deleting a DDM Instance
- Restarting a DDM Instance
- Reloading Table Data
- Scaling Out a DDM Instance
- Scaling in a DDM instance
- Modifying the Read Policy of the Associated DB Instance
- Synchronizing Data Node Information
- Querying Nodes of a DDM Instance
- Querying Details of a DDM Instance Node
- Querying Parameters of a Specified DDM Instance
- Modifying Parameters of a DDM Instance
- Querying DDM Engine Information
- Querying DDM Node Classes Available in an AZ
- Changing the Node Class of a DDM Instance
- Obtaining the Instance Group Information
- Creating an Instance Group
- Schemas
- Accounts
- Monitoring
- Session Management
- Application Examples
-
DDM Instances
- Permissions Policies and Supported Actions
- Appendix
- SDK Reference
-
Best Practices
- Overview
- Formulating Sharding Rules
- Determining the Number of Shards in a Schema
- Using Broadcast and Unsharded Tables
- Transaction Models
- SQL Standards
- Migrating an Entire RDS Database to DDM
- Migrating an Entire MyCat Database to DDM
- Accessing DDM Using a JDBC Connection Pool
- Logging In to a DDM Instance Using Navicat
- Migrating Data from RDS for MySQL to DDM Using DRS
- Sharding Database and Table Data of an RDS for MySQL Instance
- Performance White Paper
-
FAQs
- General Questions
-
DDM Usage
- How Does DDM Perform Sharding?
- What Do I Do If I Fail to Connect to a DDM Instance Using the JDBC Driver?
- Why It Takes So Long Time to Export Data from MySQL Using mysqldump?
- What Do I Do If a Duplicate Primary Key Error Occurs When Data Is Imported into DDM?
- What Should I Do If an Error Message Is Returned When I Specify an Auto-Increment Primary Key During Migration?
- What Do I Do If an Error Is Reported When Parameter Configuration Does Not Time Out?
- Which Should I Delete First, a Schema or its Associated RDS Instances?
- Can I Manually Delete Databases and Accounts Remained in Data Nodes After a Schema Is Deleted?
- SQL Syntax
-
RDS-related Questions
- Is the Name of a Database Table Case-Sensitive?
- What Risky Operations on RDS for MySQL Will Affect DDM?
- How Do I Handle Data with Duplicate Primary Keys in a Table?
- How Can I Query RDS for MySQL Information by Running Command show full innodb status?
- What Should I Pay Attention to When Selecting RDS for MySQL Instance Specifications?
- Connection Management
- Resource Freezing, Release, Deletion, and Unsubscription
- Videos
-
More Documents
-
User Guide (ME-Abu Dhabi Region)
- Service Overview
- Getting Started
- Function Overview
- Instance Management
-
Parameter Template Management
- Creating a Parameter Template
- Editing a Parameter Template
- Comparing Two Parameter Templates
- Viewing Parameter Change History
- Replicating a Parameter Template
- Applying a Parameter Template
- Viewing Application Records of a Parameter Template
- Modifying the Description of a Parameter Template
- Deleting a Parameter Template
- Task Center
- Schema Management
- Account Management
- Backup Management
- Monitoring Management
- Auditing
-
SQL Syntax
- Introduction
- DDL
- DML
- Functions
- Unsupported Items
- Supported SQL Statements
- Global Sequence
- Database Management Syntax
- Advanced SQL Functions
-
FAQs
- General Questions
-
DDM Usage
- How Can I Rectify a Fault in Accessing DDM by Using the JDBC Driver?
- What Version and Parameters Should I Select?
- Why It Takes So Long Time to Export Data from MySQL Using mysqldump?
- How Should I Handle the Duplicate Primary Key Error Occurring After Data Is Imported into DDM?
- What Should I Do If an Error Message Is Returned After I Specify an Auto-Increment Primary Key?
- How Do I Handle the Error Reported When Parameter Configuration Does Not Time Out?
- Which Should I Delete First, Schema or Associated RDS DB Instances?
- Should I Manually Delete Databases and Accounts Remained in the Associated RDS DB Instances After a Schema Is Deleted?
- SQL Syntax
- RDS-related Questions
- Connection Management
-
User Guide (Kuala Lumpur Region)
- Service Overview
- Getting Started
- Function Overview
- Instance Management
-
Parameter Template Management
- Creating a Parameter Template
- Editing a Parameter Template
- Comparing Two Parameter Templates
- Viewing Parameter Change History
- Replicating a Parameter Template
- Applying a Parameter Template
- Viewing Application Records of a Parameter Template
- Modifying the Description of a Parameter Template
- Deleting a Parameter Template
- Task Center
- Schema Management
- Account Management
- Backup Management
- Monitoring Management
- Auditing
-
SQL Syntax
- Introduction
- DDL
- DML
- Functions
- Unsupported Items
- Supported SQL Statements
- Global Sequence
- Database Management Syntax
- Advanced SQL Functions
-
FAQs
- General Questions
-
DDM Usage
- How Can I Rectify a Fault in Accessing DDM by Using the JDBC Driver?
- What Version and Parameters Should I Select?
- Why It Takes So Long Time to Export Data from MySQL Using mysqldump?
- How Should I Handle the Duplicate Primary Key Error Occurring After Data Is Imported into DDM?
- What Should I Do If an Error Message Is Returned After I Specify an Auto-Increment Primary Key?
- How Do I Handle the Error Reported When Parameter Configuration Does Not Time Out?
- Which Should I Delete First, Schema or Associated RDS DB Instances?
- Should I Manually Delete Databases and Accounts Remained in the Associated RDS DB Instances After a Schema Is Deleted?
- SQL Syntax
- RDS-related Questions
- Connection Management
-
API Reference (Kuala Lumpur Region)
- Before You Start
- API Overview
- Calling APIs
-
DDM Instance Management
- Querying DDM Engine
- Querying the Quota of Classes Available in Each AZ
- Creating a DDM Instance
- Querying DDM Instances
- Viewing Details of a DDM Instance
- Modifying the Name of a DDM Instance
- Modifying the Security Group of a DDM Instance
- Deleting a DDM Instance
- Restarting a DDM Instance
- Reloading Table Data
- Scaling Out a DDM instance
- Scaling In a DDM instance
- Modifying the Read Policy of the Associated DB Instance
- Synchronizing DB Instance Data
- Querying Nodes of a DDM Instance
- Querying Details of a DDM Instance Node
- Querying Parameters of a Specified DDM Instance
- Modifying Parameters of a DDM Instance
- Schema Management
- Account Management
- Monitoring Management
- Permissions Policies and Supported Actions
- Appendix
- Change History
-
User Guide (ME-Abu Dhabi Region)
- General Reference
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Core Functions
Function |
Description |
---|---|
Horizontal sharding |
Select a sharding key when creating a logical table. DDM will generate a sharding rule and horizontally shard data. A sharding key is a table field used to generate a route during horizontal partitioning of logical tables. After specifying a table field, you can select a date function or manually enter date function (field name). The table field must be date, datetime, or timestamp. Select a date function if data needs to be redistributed by year, month, day, week, or some combinations thereof. |
Flexible shard configuration |
DDM supports both compute and storage scaling. You can add nodes to a DDM instance or scale up its node class. Alternatively, increase shards or data nodes to distribute data from one large table to multiple tables or scale out storage resources. Compute scaling is undetectable to your applications. Storage scaling minimizes service interruption to seconds. |
Distributed transactions |
DDM processes three types of transactions, including single-shard, FREE, and Extended Architecture (XA).
|
Data import and export |
External data can be imported into DDM instances to help you migrate databases to the cloud, and DDM instance data can be exported based on service requirements. For details, see Data Migration. |
Highly compatible SQL syntax |
DDM is compatible with MySQL 5.7 and 8.0 licenses and syntax. |
Read and write splitting |
Read and write requests can be split without modifying the application code, and this is totally transparent to applications. You only need to create read replicas for a MySQL instance associated with your DDM instance and configure a read policy, and a large number of concurrent requests can read data from those read replicas. |
Global sequence |
DDM allows you to use globally unique, distributed, and ascending SNs as primary or unique keys or to meet your requirements in specific scenarios. |
Online monitoring |
DDM monitors reads, writes, and slow query logs of your DDM instance on the console, helping you detect resource and performance bottlenecks as fast as possible. |
O&M console |
DDM enables you to manage and maintain DDM instances, schemas, and accounts on a visualized console. |
Related Services
- VPC
DDM instances are deployed in an isolated VPC and you can configure IP addresses and bandwidth for accessing these DDM instances and use a security group to control access to them.
- ECS
You can access your DDM instance through an ECS.
- Relational Database Service (RDS)
After you buy a DDM instance, you can associate it with RDS for MySQL instances in the same VPC to obtain separated storage resources.
- Cloud Eye
Cloud Eye monitors DDM metrics and sends notifications in the event of an alarm or event.
- Cloud Trace Service (CTS)
CTS records operations on your DDM resources for later query, audit, and backtrack.
- Elastic Load Balance (ELB)
ELB distributes incoming traffic to multiple backend servers based on forwarding policies to balance workloads. So, it can expand external service capabilities of DDM and eliminate single points of failure (SPOFs) to improve service availability.
- Data Admin Service (DAS)
DAS provides a GUI interface for you to connect to and manage cloud databases.
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