postgresqlplpgsqlcascading-deletespostgresql-9.3

How to check if deletion is caused by CASCADE in PostgreSQL trigger

In PL/pgSQL trigger function, is there a way to know that the deletion was invoked by cascading delete action?
I have a number of checks in a trigger function to see if deletion is allowed, which I don't want to perform if the deletion is cascading from master table.

Solution

  • I can't think of a built-in way to check that.
    You could instead check for existence of the master row in the master table ...

    IF EXISTS (
   SELECT FROM master_table m
   WHERE  m.master_id = OLD.master_id
   ) THEN

   -- run checks

END IF;

    If it's a cascading delete the master row should be gone already.