Question

Is it possible to store different select value to the same variable?

DECLARE @cout int 

SELECT @cout= count(*) FROM Master1 WHERE (...)

SET @cout = SELECT count(*) FROM Master2 WHERE (...)

SET @cout = SELECT count(*) FROM Master3 WHERE (...)

IF(@cout = 0)
 BEGIN
 END

Answer 1

How about:

IF EXISTS
(
SELECT 1 FROM Master1 WHERE (...)
UNION ALL
SELECT 1 FROM Master2 WHERE (...)
UNION ALL
SELECT 1 FROM Master3 WHERE (...)
)    
BEGIN
...
END

It should do the trick, and pull out quickly enough…