mysql存储过程学习

# 创建一个名为procedure_test 存储过程。
DELIMITER $$

CREATE
    PROCEDURE `test`.`procedure_test`()
    BEGIN
	SELECT * FROM blogs;
    END$$

DELIMITER ;

#调用存储过程
CALL procedure_test();

　　

 #删除存储过程
DROP PROCEDURE procedure_test;

　　

#输出变量

DELIMITER $$
CREATE PROCEDURE `test`.`procedure_test2`(
	OUT pl DECIMAL(8,2), #输出参数1
	OUT ph DECIMAL(8,2), #输出参数2
	OUT pa DECIMAL(8,2)  #输出参数3
)
BEGIN
	SELECT MIN(prod_price)
	INTO pl  #传值1
	FROM products;
	SELECT MAX(prod_price)
	INTO ph #传值2
	FROM products;
	SELECT AVG(prod_price)
	INTO pa #传值3
	FROM products;
END $$
DELIMITER $$

　　

#创建输入输出存储过程
DELIMITER $$

CREATE PROCEDURE procedure_test3(
IN onnumber INT, #输出值
OUT ototal DECIMAL(8,2) #输出值
)
	BEGIN
	SELECT SUM(item_price * quantity)
	FROM orderitems
	WHERE order_num = onnmuber
	INTO ototal;
	END$$

DELIMITER $$

#调用存储过程
CALL procedure_test3(20005 ,@total);

#查看结果
select @total;