On Sat, Dec 22, 2012 at 9:31 AM, Adrian Klaver <adrian.klaver@xxxxxxxxx> wrote: > On 12/21/2012 02:22 PM, Chris Angelico wrote: >> As I understand it, there are three keywords: VOLATILE, STRICT, and >> IMMUTABLE. Putting one of those keywords into the declaration flags >> the function accordingly; if none is given, VOLATILE is assumed. >> >> Declaring the function as "STRICT IMMUTABLE" or "STRICT VOLATILE" >> seems at best redundant (the word "STRICT" is mere noise), and at >> worst confusing (the parser might be interpreting it as "STRICT", not >> as the other keyword). Or is there something I'm missing here? > > > Not sure I am following. > > IMMUTABLE/VOLATILE/STABLE deal with the query optimizer. > > CALLED ON NULL INPUT/STRICT deal with NULL input behavior. > > http://www.postgresql.org/docs/9.2/interactive/sql-createfunction.html OOPS! Error's mine, sorry everyone! I thought the keyword was STRICT, but it's actually STABLE that does that. Apologies to anyone who's been confused by my miswording in this thread! STRICT VOLATILE makes perfect sense; STABLE VOLATILE is what doesn't. ChrisA -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
