On Fri, Sep 9, 2011 at 9:41 PM, Roman <zo...@oe-it.ru> wrote: > Query > select null union select 4 > is Ok but > select null union select null union select 4 > is Fail > > i think it`s a bug because you choose type in second query twice > null and null -> text > text and int -> fail
Yeah, this is lousy. Unfortunately, it's also not easy to fix, so I think we're stuck with it for now. You can fix it by casting the NULL constants to int, e.g.: SELECT null::int4 UNION SELECT null::int4 UNION SELECT 4 > and i think what check type category is not true, because i can`t create > implicit cast to resolve some problems, like > select 'a' union select 4 > if i have implicit cast int->text i think it must work!! > > Sorry second part is not bug it`s a feature but it`s my problem too Sadly, I don't think that'll work - the undecorated literal is going to be treated as "unknown", not text. Implicitly casting int to text is maybe not a good idea; we removed those casts on purpose in PostgreSQL 8.3. But if you want to restore (much of) the pre-8.3 behavior, you might want to have a look at this blog post: http://petereisentraut.blogspot.com/2008/03/readding-implicit-casts-in-postgresql.html But in this case I think you're likely to still need a cast in there somewhere. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
