mysql從表中刪除重複行

Question

我有下表。我需要刪除基於zip列的重複行。

id  state  zip 
1  CA   112233 
2  CA   112233 
3  CA   112233 
4  CA   113300 
.  .   . 
.  .   . 
999  FL   345678 
1000 FL   234579 

謝謝！

Answer 1

更簡單的方法是找出你需要保持的....試試這個

DELETE FROM `you-table` 
WHERE 
    id not in (
       select * 
        from(
         SELECT 
          min(t.id) as keepID 
         from 
          `you-table` as t 
         group by concat(t.state,t.zip) 
        ) as keepTable 
      ) 

Answer 2

如果重複的次數是低，你可以重複此命令你需要，否則到時候你shuold使用迭代

delete from yourTable AS a where a.id in (select max(b.id) from yourTable AS b 
group by b.zip having count(b.id) >1); 

小心嘗試之前進行復印。