去重語句

1. 查詢重複資料：

2. 指令碼如下：

DELETE from 表 WHERE (欄位) IN ( SELECT 欄位 FROM 表 GROUP BY 欄位 HAVING COUNT(欄位) > 1) AND ROWID NOT IN (SELECT MIN(ROWID) FROM 表 GROUP BY 欄位 HAVING COUNT(*) > 1);

3.修改指令碼：

 DELETE from card_imp

 WHERE (cardno) IN (SELECT cardno FROM card_imp GROUP BY cardno HAVING COUNT(cardno) > 1)

   AND ROWID NOT IN

       (SELECT MIN(ROWID) FROM card_imp GROUP BY cardno HAVING COUNT(*) > 1);

4.查詢結果：