指定カラムに重複があるかどうか調べる
select COL_NAME from TABLE_NAME
where COL_NAME in
(select COL_NAME from TABLE_NAME group by COL_NAME
having count(*) > 1);
お好みでdistinctをつけたりしても風流。
select COL_NAME from TABLE_NAME
where COL_NAME in
(select COL_NAME from TABLE_NAME group by COL_NAME
having count(*) > 1);
お好みでdistinctをつけたりしても風流。