select num=a ,count=count(a) from
(select col1 as a from tbl_A union all
select col2 as a from tbl_A union all
select col3 as a from tbl_A ) t group by t.a
(select col1 as a from tbl_A union all
select col2 as a from tbl_A union all
select col3 as a from tbl_A ) t group by t.a
解决方案 »
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