1.支持單條件或者多條件，查找重復(fù)記錄，語(yǔ)句：

select * from stock a  
where (a.state,a.org_id,a.material_id) 
in  (select state,org_id,material_id from stock 
where state = 1 group by state,org_id ,material_id  having count(*) > 1)  

    其中“a.state”、“a.org_id”、“material_id”,為條件查詢(xún)，也就是這三個(gè)調(diào)件相同。

2.刪除重復(fù)記錄并且只留一條記錄

delete from stock   
where (org_id,material_id,state) 
in  (SELECT * from 
(select org_id,material_id, state from stock WHERE state = 1 group by org_id,material_id,state having count(*) > 1)
 a) 
and stock_id 
not in (SELECT * from
(select min(stock_id) from stock where state = 1 group by org_id,material_id,state having count(*)>1) b
)