Re: exclusive OR possible within a where clause?
От | Ken Tanzer |
---|---|
Тема | Re: exclusive OR possible within a where clause? |
Дата | |
Msg-id | CAD3a31XrnhARSRAydokSUc_U=Ar9EC=QxRNP6+PtsskT4pqQRw@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: exclusive OR possible within a where clause? (David Salisbury <salisbury@globe.gov>) |
Список | pgsql-general |
If you don't care about which row you get, how about adding a "LIMIT 1" to your query? Don't know if that counts as "messy" or not... :)
On Mon, Oct 17, 2011 at 12:15 PM, David Salisbury <salisbury@globe.gov> wrote:
Thanks for the replies!
On 10/14/11 10:58 AM, David Fetter wrote:On Thu, Oct 13, 2011 at 07:49:59PM -0400, Tom Lane wrote:David Salisbury<salisbury@globe.gov> writes:Short version, is there a way to implement an exclusive OR in a where clause?
The boolean<> operator will do the trick.
(x = y)<> (a = b)
regards, tom lane
Factoring in NULLable columns, that's:
(x IS NOT DISTINCT FROM y)<> (a IS NOT DISTINCT FROM b)
Cheers,
David.
I should note ( for the mail list archives I guess )
that the above suggestions don't work. Both rows are
returned whether I use OR or <>, though maybe I'm not
understanding something. I'm not sure why <> would work either,
as all I can find is <> is the same as !=, which is
different than the fabled XOR I was hoping for. In fact
they would never equal.
But in the end it looks like wrapper sql around my output using
"select distinct.." should do the trick.
-Dave
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