1、查詢表中多餘的重複記錄，重複記錄是根據單個欄位（Id）來判斷

select * from tablename where Id in (select Id from tablename group byId having count(Id) > 1) [and age > 10]；

2、刪除表中多餘的重複記錄，重複記錄是根據單個欄位（Id）來判斷，只留有rowid最小的記錄

DELETE from tablename WHERE (id) IN ( SELECT id FROM tablename GROUP BY id HAVING COUNT(id) > 1
 
) AND ROWID NOT IN (SELECT MIN(ROWID) FROM tablename GROUP BY id HAVING COUNT(*) > 1) [and age > 10];

3、查詢表中多餘的重複記錄（多個欄位）

select * from tablename a where (a.Id,a.seq) in(select Id,seq from tablename group by Id,seq having count(*) > 1) [and age > 10]；

4、刪除表中多餘的重複記錄（多個欄位），只留有rowid最小的記錄

delete from tablename a where (a.Id,a.seq) in (select Id,seq from tablename group by Id,seq having count(*) > 1) and rowid not in (select min(rowid) from tablename group by Id,seq having count(*)>1) [and age > 10];

5、查詢表中多餘的重複記錄（多個欄位），不包含rowid最小的記錄

select * from tablename a where (a.Id,a.seq) in (select Id,seq from tablename group by Id,seq having count(*) > 1) and rowid not in (select min(rowid) from tablename group by Id,seq having count(*)>1) [and age > 10];