Re: [SPAM]Re: Questions about 9.0 release note - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: [SPAM]Re: Questions about 9.0 release note
Date
Msg-id 201004050210.o352AmQ05766@momjian.us
Whole thread Raw
In response to Re: [SPAM]Re: Questions about 9.0 release note  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: [SPAM]Re: Questions about 9.0 release note  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> > +     Exclusion constraints ensure that if any two rows are compared on
> > +     the specified columns or expressions using the specified operators,
> > +     at least one of these operator comparisons will be false. The syntax is:
> 
> Isn't that phrasing outright incorrect?  Consider nulls.

Well, doesn't a comparison returning null really behave as false? 
Should I reword it as "not true" or "false or null"?

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com


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