要篩選重復數據,可以使用以下方法:
SELECT column1, column2, COUNT(*)
FROM table_name
GROUP BY column1, column2
HAVING COUNT(*) > 1;
SELECT t1.column1, t1.column2
FROM table_name t1
INNER JOIN (
SELECT column1, column2
FROM table_name
GROUP BY column1, column2
HAVING COUNT(*) > 1
) t2 ON t1.column1 = t2.column1 AND t1.column2 = t2.column2;
這些方法可以幫助你找出表中重復的數據,并進一步處理或刪除這些重復數據。