ALTER DATABASE

Description

This statement is used to set the properties of a specified db, change the db name, and set various quotas for the db.

Syntax

ALTER DATABASE <db_name> RENAME <new_name>
ALTER DATABASE <db_name> SET { DATA | REPLICA | TRANSACTION } QUOTA <quota>
ALTER DATABASE <db_name> SET <PROPERTIES> ("<key>" = "<value>" [, ...])

Required parameters

** 1. <db_name>**

Specifies the identifier for the database to alter.

** 2. <new_db_name>**

Specifies the new identifier for the database

** 3. <quota>**

Database data volume quota or database replica number quota

** 4. <PROPERTIES>**

Additional information about this database

Permission Control

The user executing this SQL command must have at least the following permissions:

Permissions	Object	Notes
ALTER_PRIV	Corresponding database	You need to have the permission to change the corresponding database.

Precautions

After renaming the database, use the REVOKE and GRANT commands to modify the corresponding user permissions if necessary. The default data volume quota for a database is 1024 GB, and the default replica number quota is 1073741824.

Example

• Set the data volume quota for the specified database

    ALTER DATABASE example_db SET DATA QUOTA 10995116277760;

• Rename the database example_db to example_db2

    ALTER DATABASE example_db RENAME example_db2;

• Set a quota for the number of copies of a specified database

    ALTER DATABASE example_db SET REPLICA QUOTA 102400;

• Modify the default replica distribution strategy of the table under db (this operation is only effective for newly created tables and will not modify existing tables under db)

    ALTER DATABASE example_db SET PROPERTIES("replication_allocation" = "tag.location.default:2");

• Cancel the default replica distribution policy of the table under db (this operation is only effective for newly created tables and will not modify existing tables under db)

    ALTER DATABASE example_db SET PROPERTIES("replication_allocation" = "");