存储过程使用来自不同表的数据

Question

我有存储过程。我如何调用此过程从不同的表中获取数据。 idGroup是来自不同表的列名。

    DROP PROCEDURE IF EXISTS `simpleproc`;
DELIMITER ;;
CREATE DEFINER=`sa`@`192.168.1.253` PROCEDURE `simpleproc`(IN idGroup INT, IN groupName varchar(20),IN beginDate date, IN weekday1 INT, IN weekday2 INT, IN lessonCount INT)
BEGIN
DECLARE i int;
DECLARE name1 int;
DECLARE price int;

SET  i:=1;
WHILE i<=lessonCount  DO
  SET beginDate:=DATE_ADD(beginDate,INTERVAL 1 DAY);
  IF WEEKDAY(beginDate) in(weekday1,weekday2) THEN
    SET name1:=groupName+i; 
    SET price:=price DIV 8;
    insert into lessons (lessonName, idGroup, lessonPrice, datePassed) 
      values (name1,idGroup,price,begindate);
  END IF;
  SET i:=i+1;
END WHILE;
END
;;
DELIMITER ;