- What's New
- Service Overview
- Getting Started
-
User Guide
- Function Overview
- Permissions Management
-
Instance Management
- Buying a DDM Instance
- Splitting Read-only and Read-Write Services
- Changing Class of a DDM Node
- Scaling Out a DDM Instance
- Scaling In a DDM Instance
- Changing Billing Mode of a DDM Instance
- Renewing a DDM Instance
- Restarting a DDM Instance
- Unsubscribing from a DDM Instance
- Deleting a DDM Instance
- Modifying Parameters of a DDM Instance
- Splitting Read and Write Requests
- Configuring a Parameter Template
- Connection Management
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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
- Shard Configuration
- Data Node Management
- Account Management
- Backups and Restorations
-
Data Migration
- Overview
- Migration Evaluation
- Scenario 1: Migrating Data from Huawei Cloud RDS to DDM
- Scenario 2: Migrating Data from an On-Premises RDS Instance for MySQL to DDM
- Scenario 3: Migrating Data from a Third-Party RDS for MySQL Instance to DDM
- Scenario 4: Migrating Data from a Self-Built MySQL Instance to DDM
- Scenario 5: Migrating Data from Heterogeneous Databases to DDM
- Scenario 6: Exporting Data from a DDM Instance
- Slow Queries
- Monitoring Management
- Auditing
-
SQL Syntax
- Introduction
- DDL
- DML
- Functions
- Use Constraints
- Supported SQL Statements
- Global Sequence
- Database Management Syntax
- Advanced SQL Functions
- Quotas
- Change History
-
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
- 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 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
- Schemas
- DDM Accounts
- Monitoring
-
DDM Instances
- APIs (Unavailable Soon)
- Appendix
- Change History
- 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
- Performance White Paper
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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?
- What Version and Parameters Should I Select?
- 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
- Connection Management
- Resource Freezing, Release, Deletion, and Unsubscription
- Change History
- Videos
Show all
Function Overview
Distributed Database Middleware (DDM) is a MySQL-compatible, distributed middleware service designed for relational databases. It can resolve distributed scaling issues to break through capacity and performance bottlenecks of MySQL databases, helping handle highly concurrent access to massive volumes of data.
Table 1 lists the functions supported by DDM.
Category |
Function |
---|---|
Permissions |
Creating a user and granting the user permissions to use DDM and DDM custom policies. For details, see Permissions Management. |
Instances |
Creating, deleting, renewing, unsubscribing from, and restarting a DDM instance, and changing class of a DDM instance. For details, see Instance Management. |
Backups |
Restoring data to a new DDM instance and restoring metadata For details, see Backups and Restorations. |
Parameter templates |
Creating, editing, replicating, and applying a parameter template, and comparing two parameter templates. For details, see Parameter Template Management. |
Task center |
Enabling you to view progress and statuses of asynchronous tasks submitted on the console. For details, see Task Center. |
Schemas |
Creating, exporting, importing, and deleting schemas. For details, see Schema Management. |
Flexible shards configuration for a schema |
You can increase shards or data nodes to scale out storage. For details, see Shard Configuration. |
Accounts |
Creating, modifying, and deleting a DDM account, and resetting its password. For details, see Account Management. |
Data migration |
Migrating data from Huawei Cloud and a third-party cloud to DDM or exporting data from DDM. For details, see Data Migration. |
Monitoring |
Providing metrics and methods of viewing metrics. For details, see Monitoring Management. |
SQL syntax |
Describing DDL, DML, global sequence, SQL statements, and sharding algorithms. For details, see SQL Syntax. |
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