RE: how to create this trigger?

Did you insert a row into table2?  What happens if there is no row in table 
1 where id = code (of the newly inserted row in table2).  Seems to me you 
many need to consider expanding increment_value() to check table1 to see if 
code exists.  If not insert a new value, else update.

-----Original Message-----
From:    Ramiro Arenas Ramirez [SMTP:ramiroa@coordinadora.com.co]
Sent:    Thursday, February 01, 2001 2:48 PM
To:    pgsql-sql@postgresql.org
Subject:    how to create this trigger?

I need to create a trigger that increment a value in a column
of table1 where a row is inserted in table 2

I have tried whit this but it just does nothing.

CREATE FUNCTION increment_value () RETURNS opaque AS
'DECLARE  code int4;  BEGIN  code := new.code;  UPDATE table1  SET value = value + 1  WHERE id = code;
RETURN NEW;
END;'  LANGUAGE 'plpgsql';

CREATE TRIGGER insert_on_table2 BEFORE INSERT ON table2FOR EACH ROW EXECUTE PROCEDURE increment_value();


Can you help me?