Re: ORDER BY user defined function performance issues

От: Tom Lane
Тема: Re: ORDER BY user defined function performance issues
Дата: ,
Msg-id: 16729.1086976782@sss.pgh.pa.us
(см: обсуждение, исходный текст)
Ответ на: ORDER BY user defined function performance issues  (Nick Trainor)
Список: pgsql-performance

Nick Trainor <> writes:
> What am I missing here?

The ORDER BY query has to evaluate the function at *every* row of the
table before it can sort.  The other query was only evaluating the
function at twenty rows.

            regards, tom lane


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