oracle过滤重复数据，只保留一条

 select * from t_case where CAR_NUMBER in (select CAR_NUMBER from t_case group by CAR_NUMBER having count(CAR_NUMBER) > 1)
    
    

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

语句如上，我就不多解释了。