比如以下SQL语句：
SELECT TMPTABLE.COL_A,
TMPTABLE.COL_B,
TMPTABLE.COL_Z,
TMPTABLE.COL_M,
TEST_A.COL_C
FROM TEST_A,
(SELECT TEST_C.COL_A COL_A, <------ 重点在此处
TEST_C.COL_B COL_B,
TEST_B.COL_Z COL_Z,
MAX(TEST_C.COL_M) COL_M
FROM TEST_A, TEST_B,TEST_C
WHERE TEST_B.COL_X = TEST_C.COL_X
GROUP BY COL_A, COL_B, COL_Z ) TMPTABLE
WHERE TEST_A.COL_A = TMPTABLE.COL_A AND
TEST_A.COL_B = TMPTABLE.COL_B
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不支持。(其实你试试就知道了)
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考虑用视图完成，我以前就是这样做的，有点麻烦 :(