tuning

Hello,
I have the following statement:

select 'A', t1.* from table1 t1
UNION
select 'B', t2.* from table2 t2;

Each select statement is running ok, but together with the UNION it takes much too long. How can I tune something like this? Thanks in advance
Corinna Becker Received on Tue Oct 13 1998 - 04:34:46 CDT