could I get some guidance on the best approach on how to execute a block of PL/SQL in SP?

For example:
I have the following SQL block:
update table1 set TOTAL_RETURN = TOTAL_RETURN*0.5;
select * from table1 where id='10';

I need to be able to execute this code in one session and not split it up. It seems I cannot include more than one SQL statement in the dclsql section of a bdf script.

PS: I'm using SP 7.3.1 and testing against Oracle 10g.