Call multiple functions from trigger?

11 votes

2 answers

22218 views

                          I run **PostgreSQL-9.2.4**

Is it possible to call 2 functions from a trigger?

Let's say I have two functions for two different tables to be executed if the following trigger fires:

**Trigger:**

    CREATE TRIGGER start ON system_status FOR EACH ROW
    WHEN ((new.event = start_task))
    EXECUTE PROCEDURE ...()

**Function 1:**
*(When task starts, remove any previously assigned next task for this system)*

    CREATE FUNCTION void_next_task() RETURNS trigger AS $$
    
    BEGIN
      DELETE FROM tasks_status ts
      WHERE ts.system = NEW.system
      AND ts.event = 'next_task';
      RETURN NEW;
      END;
    
    $$
    
    LANGUAGE plpgsql

**Function 2:**
*(If the inserted combination of task and system is already present in the table, then mark any earlier record with this combination as deleted)*

    CREATE FUNCTION void_dup_task() RETURNS trigger AS $$
    
    BEGIN
      UPDATE system_status ss
      SET deleted = 'TRUE'
      WHERE ss.system = NEW.system
      AND ss.task = NEW.task
      AND ss.deleted IS FALSE;
      RETURN NEW;
      END;
    
    $$
    
    LANGUAGE plpgsql

So I ended up with the following ways to resolve it:

 1. To have a trigger which calls two functions;
 2. To have a function which performs update on one table and delete on another one;
 3. To have two exactly same triggers and two different functions;

Before I will go ahead and implement solution 3 could you advice me if solution 1 or 2 are possible at all?

 
                        

Asked by VL-80 (213 rep)

Nov 30, 2013, 06:42 PM
Last activity: Feb 13, 2025, 05:22 PM

Call multiple functions from trigger?

Related Questions