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T-SQL XOR Operator

Is there an XOR operator or equivalent function i开发者_运维技巧n SQL Server (T-SQL)?


There is a bitwise XOR operator - the caret (^), i.e. for:

SELECT 170 ^ 75

The result is 225.

For logical XOR, use the ANY keyword and NOT ALL, i.e.

WHERE 5 > ANY (SELECT foo) AND NOT (5 > ALL (SELECT foo))


Using boolean algebra, it is easy to show that:

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


A B | f = notA and B | g = A and notB | f or g | A xor B    
----+----------------+----------------+--------+--------    
0 0 | 0              | 0              | 0      | 0    
0 1 | 1              | 0              | 1      | 1    
1 0 | 0              | 1              | 1      | 1    
1 1 | 0              | 0              | 0      | 0


As clarified in your comment, Spacemoses, you stated an example: WHERE (Note is null) ^ (ID is null). I do not see why you chose to accept any answer given here as answering that. If i needed an xor for that, i think i'd have to use the AND/OR equivalent logic:

WHERE (Note is null and ID is not null) OR (Note is not null and ID is null)

That is equivalent to:

WHERE (Note is null) XOR (ID is null)

when 'XOR' is not available.


MS SQL only short form (since SQL Server 2012):

1=iif( a=b ,1,0)^iif( c=d ,1,0)


The xor operator is ^

For example: SELECT A ^ B where A and B are integer category data types.


It is ^ http://msdn.microsoft.com/en-us/library/ms190277.aspx

See also some code here in the middle of the page How to flip a bit in SQL Server by using the Bitwise NOT operator


<> is generally a good replacement for XOR wherever it can apply to booleans.


From your comment:

Example: WHERE (Note is null) ^ (ID is null)

you could probably try:

where
   (case when Note is null then 1 else 0 end)
 <>(case when ID is null then 1 else 0 end)
0

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