-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Tom Lane wrote: > Gaetano Mendola <[EMAIL PROTECTED]> writes: >> I can immagine a case when a lower module exports a view to upper layer >> stating >> the interface as list of fields: > >> first_name, last_name, .... > >> with an *hidden* field that is a function call that updates the statistics on >> how many time a given record was selected, then this technique can not be >> used >> anymore starting with 8.2.x. > > You're living in a dream world if you think that works reliably in *any* > version of Postgres. But for starters, what is your definition of > "selected" --- pulled from the physical table? Accumulated into an > aggregate? Delivered as a recognizable row to the client? Delivered N > times to the client due to joining N times to some other table?
Well that was a not good example, I don't have any problem in mark from now on all my function as stable/immutable (the one I use on views) but still I believe is source of bad performance evaluate a function on rows discarded and at same time this break the principle of least surprise. Regards Gaetano Mendola -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFF9U8R7UpzwH2SGd4RAhoGAKDSpUSQ3lGEdIdFWLwQjxoZXUAS1ACdGtht TZg9BKScbzGO0MzpHy0Gr80= =auwk -----END PGP SIGNATURE----- ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
