ALTER USER MAPPING
Function
ALTER USER MAPPING changes the definition of a user mapping.
Precautions
If the password option is displayed, ensure that the usermapping.key.cipher and usermapping.key.rand files exist in the $GAUSSHOME/bin directory of each node in openGauss. If the two files do not exist, use the gs\_guc tool to generate them and use the gs\_ssh tool to release them to the $GAUSSHOME/bin directory on each node.
Syntax
ALTER USER MAPPING FOR { user_name | USER | CURRENT_USER | PUBLIC }
SERVER server_name
OPTIONS ( [ ADD | SET | DROP ] option ['value'] [, ... ] )
In OPTIONS, ADD, SET, and DROP are operations to be performed. If these operations are not specified, ADD operations will be performed by default. option and value are the parameters and values of the corresponding operation.
Parameter Description
user_name
Specifies user name of the mapping.
CURRENT_USER and USER match the name of the current user. PUBLIC is used to match all current and future user names in the system.
server_name
Specifies name of the server to which the user is mapped.
OPTIONS
Changes an option for the user mapping. The new option overwrites any previously specified option. ADD, SET, and DROP are operations to be performed. If the operation is not set explicitly, ADD is used. The option name must be unique and will be validated with the foreign data wrapper of the server.
Options supported by oracle_fdw are as follows:
user
Oracle server user name.
password
Password of the Oracle user.
Options supported by mysql_fdw are as follows:
username
User name of the MySQL server or MariaDB.
password
User password of the MySQL server or MariaDB.
Options supported by postgres_fdw are as follows:
user
User name of the remote openGauss database.
password
User password of the remote openGauss database.