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

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6: Re: Limitation on length of bind variables (response to 1)
Posted by Don Baccus on 02/25/04 11:02 PM
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.

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9: Re: Limitation on length of bind variables (response to 6)
Posted by Andrew Piskorski on 02/25/04 11:40 PM
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?