Trigger syntax

(Oracle 7.3.4 for NT)

I have two tables tab1 and tab2.

What I want to be able to do is create a database trigger that increments a sequence in tab1 when a row is inserted in tab2 but only were there is currently no value in tab1. (There is a one to many relationship between tab1 and tab2).

I can do it easily if I only had one table with something like:

create or replace trigger foo_tg
before insert on tab1
for each row
begin

        select foo_seq.nextval into :new.field from dual; end;

but I'm stuck - not even sure if I'm going the right way about achieving what I need.

Any advice would be greatly appreciated.

regards

Chris Received on Thu Aug 02 2001 - 13:51:11 CDT