sql删除重复数据,只剩下一条记录的语句

--查找重复数据

select *
  from canteen_book a
 where (a.name, a.booktime,a.type) in (select name, booktime,type
                                 from canteen_book
                                group by name, booktime,type
                               having count(*) > 1)


----删除重复数据
delete from canteen_book a
 where (a.name, a.booktime,a.type) in (select name, booktime,type
                                 from canteen_book
                                group by name, booktime,type
                               having count(*) > 1)
   and rowid not in (select min(rowid)
                       from canteen_book
                      group by name, booktime,type
                     having count(*) > 1)

适用于部分重复
上面查询 下面删除
name, booktime,type   假设三个字段有重复