Function Overview

Distributed Database Middleware (DDM) is a MySQL-compatible distributed relational database. It uses a storage-compute decoupled architecture that makes it easy to scale out compute and storage resources to handle millions of concurrent requests.

Table 1 lists the functions supported by DDM.

**Table 1** DDM functions
Category	Function
Instances	Creating, deleting, restarting, renewing, and unsubscribing from a DDM instance, and changing class of a DDM instance. For details, see Instance Management.
Backups	Backing up a DDM instance, restoring a DDM instance from a backup, and restoring data from the current DDM instance. For details, see Backup Management.
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.
Schema scaling	Scaling out a schema by rebalancing or resharding. For details, see Scaling Out a Schema.
Accounts	Creating, modifying, and deleting a DDM account, and resetting its password. For details, see Account Management.
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.