Help Center/ Distributed Database Middleware/ User Guide/ Schema Management/ Creating a Schema
Updated on 2022-09-16 GMT+08:00
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Creating a Schema

Prerequisites

  • You have logged in to the DDM console.
  • The DDM instance is in the Running state.
  • Do not modify or delete the internal accounts (DDMRW*, DDMR*, and DDMREP*) created on data nodes. Otherwise, services will be affected.
    • The internal account name is in the format: Fixed prefix (such as DDMRW, DDMR, or DDMREP) + Hash value of the data node ID.
    • A random password is generated, which contains 16 to 32 characters.
    • All DB instances associated with one schema must have the same major MySQL version.
    • Multiple schemas can be created in a DDM instance and associated with the same data node. One DDM instance can be associated with either RDS for MySQL or GaussDB(for MySQL) instances, but not both.
    • One data node cannot be associated with schemas in different DDM instances.
    • If you select Sharded for Sharding when you create a schema, the shard name follows the rule: schema+xxxx. xxxx indicates the digit increased from 0000. For example, if a schema name is db_cbb5 and the total number of shards is 2, the shard names are db_cbb5_0000 and db_cbb5_0001.

You can create a schema in two ways: on the Instances page or on the Schemas page. This section uses the Instances page as an example to describe how to create a schema.

Figure 1 Instances page
Figure 2 Schemas page

Procedure

  1. In the navigation pane, choose Instances. In the instance list, locate the DDM instance that you want to create a schema for and click Create Schema in the Operation column.
  2. On the displayed page, specify a sharding mode, enter a schema name, set the number of shards, select the required DDM accounts, and click Next.
  3. Enter the database password and click Test Connection.
  4. After the test becomes successful, click Finish.
Parent topic: Schema Management