Re: why the need for is null?
От | Baldur Norddahl |
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Тема | Re: why the need for is null? |
Дата | |
Msg-id | 1072997609.3ff4a4e90800a@localhost обсуждение исходный текст |
Ответ на | Re: why the need for is null? (Martijn van Oosterhout <kleptog@svana.org>) |
Ответы |
Re: why the need for is null?
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Список | pgsql-general |
Quoting Martijn van Oosterhout <kleptog@svana.org>: > Because in trivalued logic, <anything> = NULL is also NULL. You need a > special operator to check if something is NULL, hence IS NULL and IS NOT > NULL. SQL standard says so. > > This is a FAQ but I don't see it mentioned there. Ok, but since this can be quite annoying and unexpected, could we get an operator that does not use tristate logic but simply compares? Maybe == which seems to be free :-) So X==Y is true if X and Y are equal or both are null, false othervise. Baldur ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program.
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