SELECT a2.id,a2.ww,a2.ss,
(select a1.name FROM a1 WHERE a1.id=LEFT(a2.id,2)) 大类列,
(select a1.name FROM a1 WHERE a1.id=LEFT(a2.id,4)) 小类列
from a2
(select a1.name FROM a1 WHERE a1.id=LEFT(a2.id,2)) 大类列,
(select a1.name FROM a1 WHERE a1.id=LEFT(a2.id,4)) 小类列
from a2
解决方案 »
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