2009/2/16 Sam Mason <s...@samason.me.uk>: > On Mon, Feb 16, 2009 at 02:35:54PM +0100, Pavel Stehule wrote: >> attachment contains module that transform every empty string to null. > > Why would anyone ever want to do this? This would appear to break all > sorts of things in very non-obvious ways:
I agree, so this behave is strange - but Oracle does it. so normal query in Oracle for empty value looks like select * from people where surname is null; and some application expect transformation from '' to null. http://www.thunderguy.com/semicolon/2003/04/26/oracle-empty-string-null/ so these modules (decode, oraemptystr) decrease differences between PostgreSQL and Oracle. Regards Pavel Stehule p.s. I am not Oracle expert, I expect so here are more qualified men. > > SELECT CASE s WHEN '' THEN 'empty string' ELSE s END FROM foo; > UPDATE foo SET s = NULL WHERE s = ''; > > would no longer do the expected thing. It would only do the expected > thing (in my eyes) when strings of zero length were actually being > inserted into the database. Like: > > INSERT INTO foo (s) VALUES (''); > UPDATE foo SET s = '' WHERE s = 'empty string'; > > Or am I missing something obvious? > > -- > Sam http://samason.me.uk/ > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers > -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
