Re: NULLs ;-)
От | Ragnar |
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Тема | Re: NULLs ;-) |
Дата | |
Msg-id | 1164749939.27070.190.camel@localhost.localdomain обсуждение исходный текст |
Ответ на | Re: NULLs ;-) (Scott Ribe <scott_ribe@killerbytes.com>) |
Ответы |
Re: NULLs ;-)
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Список | pgsql-general |
On þri, 2006-11-28 at 12:28 -0700, Scott Ribe wrote: > >>> where a <> b or (a is null and b is not null) or (a is not null and > >>> b is null) > >> > >> In the absence of IS DISTINCT FROM, I think this has the same semantics: > >> > >> where coalesce(a, b) <> coalesce(b, a) > > > > sorry, but no. > > So it would have to be where coalesce(a, b, 0) <> coalesce(b, a, 0) for your > example with ints, and likewise some default value for other column types... no cigar. test=# select a,b, coalesce(a, b, 0) <> coalesce(b, a, 0) as john, a IS DISTINCT FROM b as dist from logic; a | b | john | dist ---+---+------+------ | | f | f | 1 | f | t 1 | | f | t 1 | 1 | f | f (4 rows) gnari
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