找出表中完全相同的两条记录并删除其中一条
某张table 有col1,col2,col3三个栏位
查看是否有纪录相同
select col1,col2,col3,count(*) from table group by col1,col2,col3 having count(*) >1;
删除相同的数据,只留下一笔.
DELETE TABLE
WHERE (COL1,COL2,COL3) IN
(SELECT COL1,COL2,COL3 FROM TABLE GROUP BY COL1,COL2,COL3
HAVING COUNT(*) > 1)
AND ROWID NOT IN
(SELECT MIN(ROWID) FROM TABLE GROUP BY COL1,COL2,COL3
HAVING COUNT(*) > 1)
查看是否有纪录相同
select col1,col2,col3,count(*) from table group by col1,col2,col3 having count(*) >1;
删除相同的数据,只留下一笔.
DELETE TABLE
WHERE (COL1,COL2,COL3) IN
(SELECT COL1,COL2,COL3 FROM TABLE GROUP BY COL1,COL2,COL3
HAVING COUNT(*) > 1)
AND ROWID NOT IN
(SELECT MIN(ROWID) FROM TABLE GROUP BY COL1,COL2,COL3
HAVING COUNT(*) > 1)
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/166189/viewspace-113550/ ，如需转载，请注明出处，否则将追究法律责任。
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