去重的按某个字段进行去重sql
delete from op_car_owners2 where carnum in(
select carnum from(
select max(carnum ) as carnum ,count(carnum) as count from op_car_owners2 group by carnum having count>1 order by count desc
) as tab
)
DELETE from op_car_owners2 where carnum=\'苏A9CC18\' and phone=\'0\'