mysql动态sql，存储过程动态tablename，存储过程参数为表名

DELIMITER $$DROP PROCEDURE IF EXISTS `proc`$$CREATE    PROCEDURE `ondutystatisticdb`.`proc`(tablename VARCHAR(50))    BEGIN        SET @STMT :=CONCAT(" ALTER TABLE ",tablename," DROP PRIMARY KEY;");       PREPARE STMT FROM @STMT;       EXECUTE STMT;        END$$DELIMITER ;