select 字段1,字段2,count(*) from 表名 group by 字段1,字段2 having count(*) > 1

delete from 表名 a where 字段1,字段2 in(select 字段1,字段2,count(*) from 表名 group by 字段1,字段2 having count(*) > 1)

create table 臨時(shí)表 as(select 字段1,字段2,count(*) from 表名 group by 字段1,字段2 having count(*) > 1)

delete from 表名 a where 字段1,字段2 in (select 字段1，字段2 from 臨時(shí)表);

select a.rowid,a.* from 表名 a where a.rowid != (  select max(b.rowid) from 表名 b   where a.字段1 = b.字段1 and   a.字段2 = b.字段2  )

delete from 表名 a where a.rowid !=  (  select max(b.rowid) from 表名 b   where a.字段1 = b.字段1 and   a.字段2 = b.字段2  )

create table 臨時(shí)表 as   select a.字段1,a.字段2,max(a.rowid) dataid from 正式表 a group by a.字段1,a.字段2;  delete from 表名 a  where a.rowid !=  (  select b.dataid from 臨時(shí)表 b   where a.字段1 = b.字段1 and   a.字段2 = b.字段2  ); commit;

select distinct * from 表名

create table 臨時(shí)表 as (select distinct * from 表名);  drop table 正式表;  insert into 正式表 (select * from 臨時(shí)表);  drop table 臨時(shí)表;

insert into t_table_bakselect distinct * from t_table;