user defined function speeds - Mailing list pgsql-sql

> > Good plan.  Although you could sort by a user-defined function result,
> > it's likely to be horribly slow (because user-defined functions are
> > slow:-().


What is the actual overhead from using a userdefined
function (a C function, say)?

Obviously there is an overhead involved in calling
any function. I would like to know what kind of issues
are involved when using results of a user defined function for
sorting.

Are the results calculated only once, as one would expect,
for example.

Thanks,


Troy

Troy Korjuslommi                Tksoft OY, Inc.
tjk@tksoft.com                  Software Development
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