SELECT C1,C2,C3 FROM T1 ORDER BY C1
UNION ALL
SELECT C1,C2,C3 FROM T2 ORDER BY C1
當(dāng)執(zhí)行上述SQL語(yǔ)句時(shí)醋安，會(huì)報(bào)錯(cuò)刁憋。
這時(shí)候需要使用臨時(shí)表滥嘴，如下：
SELECT * FROM
(SELECT C1,C2,C3 FROM T1 ORDER BY C1) t1
UNION ALL
SELECT * FROM
(SELECT C1,C2,C3 FROM T2 ORDER BY C1) t2
PS：UNION (ALL) 的使用條件是，列名至耻、數(shù)據(jù)類型和列數(shù)都要一一對(duì)應(yīng)若皱。
