mysql去除重复

insert into t1 values('100',1,1,'2017-01-25');insert into t1 values('100',1,1,'2017-01-25');insert into t1 values('100',1,1,'2017-01-25');insert into t1 values('100',1,1,'2017-01-25');insert into t1 values('102',1,1,'2017-01-25');insert into t1 values('102',1,1,'2017-01-25');select *  from   t1 ; create table t2 as   select *  from  t1 ; truncate  table t2 ;select  sku,PRice,cost,dt  from t1  where dt = '2017-01-25'  group by sku ; insert  into t2(sku,price,cost,dt)select  sku,price,cost,dt  from t1  where dt = '2017-01-25'  group by sku ;  select *  from   t2 ; select  sku,price,cost,dt  from t1  where dt = '2017-01-25'  group by sku,price,cost,dt ;