Forum OpenACS Q&A: Re: Tricky query port (pg -&amp;gt; oracle)
Weird... I have no idea why you can't use subqueries as columns in PL/SQL.AFAIK, in Oracle 8i PL/SQL and SQL use different parsers, and the PL/SQL parser lacks some of the features of the SQL one. The 2 parsers should be synchronized from Oracle 9i onwards.
For the original problem, maybe executing the problematic query with the 'execute immediate' construct may help: documentation for 'execute immediate' in Oracle 8i can be found here. Please let me know if it solves your problem.