ALTER DATABASE

Changes the attributes of a database.

Synopsis

  1. ALTER DATABASE <name> SET <parameter> { TO | = } { <value> | DEFAULT } 
  3. ALTER DATABASE <name> RESET <parameter>

Description

ALTER DATABASE changes the attributes of a HAWQ database.

SET and RESET changes the session default for a configuration parameter for a HAWQ database. Whenever a new session is subsequently started in that database, the specified value becomes the session default value. The database-specific default overrides whatever setting is present in the server configuration file (hawq-site.xml). Only the database owner or a superuser can change the session defaults for a database. Certain parameters cannot be set this way, or can only be set by a superuser.

Parameters

The name of the database whose attributes are to be altered.

Note: HAWQ reserves the database “hcatalog” for system use. You cannot connect to or alter the system “hcatalog” database.

Set this database’s session default for the specified configuration parameter to the given value. If value is DEFAULT or if RESET is used, the database-specific setting is removed, so the system-wide default setting will be inherited in new sessions. Use RESET ALL to clear all database-specific settings. See About Server Configuration Parameters for information about user-settable configuration parameters.

Notes

It is also possible to set a configuration parameter session default for a specific role (user) rather than to a database. Role-specific settings override database-specific ones if there is a conflict. See ALTER ROLE.

Examples

To set the default schema search path for the mydatabase database:

  1. ALTER DATABASE mydatabase SET search_path TO myschema, 
  2. public, pg_catalog;

Compatibility

The ALTER DATABASE statement is a HAWQ extension.

See Also

CREATE DATABASE, DROP DATABASE, SET