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

From Tom Lane
Subject Re: [SPAM]Re: Questions about 9.0 release note
Date
Msg-id 20897.1270478119@sss.pgh.pa.us
Whole thread Raw
In response to Re: [SPAM]Re: Questions about 9.0 release note  (Bruce Momjian <bruce@momjian.us>)
Responses Re: [SPAM]Re: Questions about 9.0 release note  (Bruce Momjian <bruce@momjian.us>)
List pgsql-hackers
Bruce Momjian <bruce@momjian.us> writes:
> 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"?

Either one.
        regards, tom lane


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