Forum OpenACS Development: Re: Limitation on length of bind variables

Posted by Don Baccus on
The table-generated-by-PL/SQL approach is faster because it transforms the IN into  a pseudo-join of the form used if you say "WHERE foo IN (SELECT bar FROM fubar)".

The "WHERE foo IN (list of literals)" approach is transformed into a bunch of OR expressions - which are always slow as hell in SQL implementations.

Posted by Andrew Piskorski on
Um, Don, then my obvious question is, why doesn't Oracle transform the "where foo in (...)" syntax into a pseudo-join as well, rather than lots of or expressions? And are PostgreSQL or other RDBMSs any smarter about that?