Re: null != null ??? - Mailing list pgsql-general

From Fran Fabrizio
Subject Re: null != null ???
Date
Msg-id 3BD98E53.FAF01D3C@mmrd.com
Whole thread Raw
In response to null != null ???  (Fran Fabrizio <ffabrizio@mmrd.com>)
List pgsql-general
> Fran Fabrizio <ffabrizio@mmrd.com> writes:
> > Can someone smarter than me tell me what I am missing?
>
> Comparisons involving NULL yield NULL.  Any book on SQL should
> explain this ...

...except 'select null=null' doesn't follow this rule (it yields 'true')
so one
can understand my confusion.  Thanks to Thomas for the explanation
and history of this interesting quirk.

-Fran



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