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Updated on 2024-06-03 GMT+08:00

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ALTER TRIGGER

Description

ALTER TRIGGER is used to change the name of a trigger.

Currently, only the trigger name can be modified.

Precautions

The owner of the table where a trigger resides or a user granted the ALTER ANY TRIGGER permission can perform the ALTER TRIGGER operation. A system administrator has this permission by default.

Syntax

    
         ALTER TRIGGER trigger_name ON table_name RENAME TO new_name;

Parameters

trigger_name
Specifies the name of the trigger to be modified.

Value range: an existing trigger
table_name
Specifies the name of the table where the trigger to be modified is located.

Value range: an existing table having a trigger
new_name
Specifies the new name after modification.

Value range: a string, which complies with the naming convention. A value contains a maximum of 63 characters and cannot be the same as other triggers on the same table.

Examples

    
         -- Create a source table and a destination table.
gaussdb=# CREATE TABLE test_trigger_src_tbl(id1 INT, id2 INT, id3 INT);
gaussdb=# CREATE TABLE test_trigger_des_tbl(id1 INT, id2 INT, id3 INT);

-- Create a DELETE trigger function.
gaussdb=# CREATE OR REPLACE FUNCTION TRI_DELETE_FUNC() RETURNS TRIGGER AS
           $$
           DECLARE
           BEGIN
                   DELETE FROM test_trigger_des_tbl WHERE id1=OLD.id1;
                   RETURN OLD;
           END
           $$ LANGUAGE plpgsql;

-- Create a DELETE trigger.
gaussdb=# CREATE TRIGGER delete_trigger BEFORE DELETE ON test_trigger_src_tbl FOR EACH ROW EXECUTE PROCEDURE tri_delete_func();

-- Rename a trigger.
gaussdb=# ALTER TRIGGER delete_trigger ON test_trigger_src_tbl RENAME TO delete_trigger_renamed;

-- Delete the trigger.
gaussdb=# DROP TRIGGER delete_trigger_renamed ON test_trigger_src_tbl;

-- Delete the function.
gaussdb=# DROP FUNCTION tri_delete_func;

-- Delete the source table and destination table.
gaussdb=# DROP TABLE test_trigger_src_tbl;
gaussdb=# DROP TABLE test_trigger_des_tbl;