VastbaseE100

ALTER TRIGGER

• ALTER TRIGGER tg_name DISABLE;

• ALTER TRIGGER tg_name ENABLE;

• ALTER TRIGGER tg_name RENAME TO tg_name1;

  CREATE TABLE student (
    id   int primary key,
    name varchar(50)
  );
  CREATE TABLE score (
    studentId  int,
     math     int 
  );
  INSERT INTO student VALUES(1,'April');
  INSERT INTO student VALUES(2,'Harris');
  INSERT INTO score VALUES(1, 98);
  INSERT INTO score VALUES(2,77);
  CREATE OR REPLACE FUNCTION student_delete_trigger()
  RETURNS TRIGGER AS $$
  BEGIN
  DELETE FROM score where studentId = OLD.id;
  RETURN OLD;
  END;
  $$
  LANGUAGE plpgsql;
  CREATE TRIGGER delete_trigger 
  AFTER DELETE ON student
  FOR EACH ROW EXECUTE PROCEDURE student_delete_trigger();
  atlasdb=# \d student
                   Table "atlasdb.student"
  Column |         Type          | Collation | Nullable | Default 
  --------+-----------------------+-----------+----------+---------
  id     | integer               |           | not null | 
  name   | character varying(50) |           |          | 
  Indexes:
  "student_pkey" PRIMARY KEY, btree (id)
  Triggers:
  delete_trigger AFTER DELETE ON student FOR EACH ROW EXECUTE PROCEDURE student_delete_trigger()
  ALTER TRIGGER delete_trigger DISABLE;
  ALTER TRIGGER delete_trigger RENAME TO delete_trigger2;	
  DELETE FROM student where id = 2;
  select * from score
  studentid | math 
  -----------+------
       1 |   98
       2 |   77
  (2 rows)
  ALTER TRIGGER delete_trigger2 ENABLE;
  DELETE FROM student where id = 1;
  select * from score
  studentid | math 
  -----------+------
       2 |   77
  (1 row)