select A,sum(B) from
(
select A,B from test1
union all
select A,B from test2
union all
select A,-B from test3
union all
select A,-B from test4
) tem group by A
(
select A,B from test1
union all
select A,B from test2
union all
select A,-B from test3
union all
select A,-B from test4
) tem group by A
解决方案 »
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