Обсуждение: XOR operator.

Does postgresql support the xor operator?

Josh.

On Fri, 28 Mar 2003, Joshua Moore-Oliva wrote:

> Does postgresql support the xor operator?

You can get bitwise/binary xor (of bitstrings and integers) with the #
operator AFAICS.

AFAICR

A xor B = ( A and not B) or ( not A and B)

It is a pain to write, but you can always:

CREATE FUNCTION XOR( boolean, boolean)
RETURNS boolean as '
RETURN ( $1 and not $2) or ( not $1 and $2);
' LANGUAGE 'plpgsql';



Stephan Szabo wrote:
>
> On Fri, 28 Mar 2003, Joshua Moore-Oliva wrote:
>
> > Does postgresql support the xor operator?
>
> You can get bitwise/binary xor (of bitstrings and integers) with the #
> operator AFAICS.
>
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On Sat, 29 Mar 2003, Jean-Luc Lachance wrote:

> AFAICR
>
> A xor B = ( A and not B) or ( not A and B)

Unless I misremember, for simple booleans
A xor B can be expressed as A!=B.  That's why I'd
guessed he was looking for bitwise/binary xor.