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[Sql]EXCEPT ºÍ INTERSECT¹Ø¼ü×Ö
http://www.cnblogs.com/treeyh/archive/2008/07/01/1232845.html
EXCEPT
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INTERSECT
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A. ʹÓà EXCEPT
ÔÚʾÀýÖÐʹÓà TableA ºÍ TableB ÖеÄÊý¾Ý¡£
TableA (col1 int)
TableB (col1 int)

NULL
NULL
NULL
1
NULL
3
1
4
2
4
2
2
3
4
4
ÒÔϲéѯ´Ó EXCEPT
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SELECT * from TableA EXCEPT
SELECT * from TableB;
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Col1
-----------
2
(1 row(s) affected)
B. ʹÓà INTERSECT
ÔÚʾÀýÖÐʹÓà TableA ºÍ TableB ÖеÄÊý¾Ý¡£
TableA (col1 int)
TableB (col1 int)

NULL
2
NULL
2
NULL
2
1
4
2
4
2
2
3
4
4
ÒÔϲéѯ·µ»Ø INTERSECT
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SELECT * from TableA INTERSECT
SELECT * from TableB;
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Col1
-----------
2
4
(2 row(s) affected)


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