MySQL 存储过程 删除重复数据 采用limit

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CREATE PROCEDURE updateBdAreaData()
BEGIN
        declare stopFlag int;
        DECLARE dataid varchar(100);
        declare repeatCount int;
        declare i int;   -- 循环变量
        -- 申明游标
        declare dataCursor cursor for
                select fid,count(1) from t_bd_newarea group by fid having count(1) > 1;

    -- 申明跳出循环
    DECLARE CONTINUE HANDLER FOR NOT FOUND set stopFlag=1;
    OPEN dataCursor;
            REPEAT
            FETCH dataCursor INTO dataid,repeatCount;
            BEGIN
                set i =repeatCount-1;
                if i = 2 THEN
delete from t_bd_newarea where fid = dataid limit 2;
                end if;
                
       
       END;
            UNTIL  stopFlag = 1  
                END REPEAT;
   CLOSE dataCursor;
END;

call updateBdAreaData();    -- 调用存储过程
COMMIT;    --提交
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