1.查看表中有木要重复数据
select column1，column2，count(*) from table group by column1 column2 having count(*) > 1;
eg.
select drill.reportfor, drill.wellbore_id, count(*)
from zj_dailydrillrep drill
group by drill.reportfor, drill.wellbore_id
HAVING count(*) > 1;
2.