# 创建存储过程 select_all_data(),查看 employees 表的所有数据 DELIMITER $ CREATEPROCEDUREselect_all_data() BEGIN SELECT*FROMemployees; END$ DELIMITER ; # 创建存储过程 avg_employee_salary(),返回所有员工的平均工资 DELIMITER// CREATEPROCEDUREavg_employee_salary() BEGIN SELECTAVG(salary)ASavg_salaryFR...
VariablesDatabaseStored_ProcedureVariablesDatabaseStored_ProcedureSELECT id, name, age INTO user_id, user_name, user_age FROM usersData is fetchedSELECT user_id, user_name, user_age 总结 通过本文的学习,我们了解了如何在MySQL存储过程中使用SELECT语句将多个字段的值赋给变量。存储过程是MySQL中非常有用...
The second test case was modified thus: create procedurebug7992_2() insert into t3 (s1) select max(t4.s1)+1 from t3 as t4; to avoid some confusion over the multiple references to the same field. (If this is a bug, it's a different one than this one in any case.)...
CREATE PROCEDURE p2 (IN parameter1 INT) BEGIN DECLARE variable1 INT; SET variable1 = parameter1 + 1; CASE variable1 WHEN 0 THEN INSERT INTO t VALUES (17); WHEN 1 THEN INSERT INTO t VALUES (18); ELSE INSERT INTO t VALUES (19); END CASE; END; // 循环语句 WHILE … END WHILE LOO...
Stored Procedure的局部变量:作用域在代码块内(begin和end之间),用declare定义。 Session级别的session变量 (session variable) 即是 用户自定义变量(User-Defined Variables):作用域在当前连接的session;变量名以@开始。 系统变量 (Server System Variables):全局或会话级。
mysql > DELIMITER // mysql > CREATE PROCEDURE proc1 --name存储过程名 -> (IN parameter1 INTEGER) -> BEGIN -> DECLARE variable1 CHAR(10); -> IF parameter1 = 17 THEN -> SET variable1 = 'birds'; -> ELSE -> SET variable1 = 'beasts'; -> END IF; -> INSERT INTO table1 VALUES ...
存储过程(Stored Procedure)是一种在数据库中存储复杂程序,以便外部程序调用的一种数据库对象。 存储过程是为了完成特定功能的SQL语句集,经编译创建并保存在数据库中,用户可通过指定存储过程的名字并给定参数(需要时)来调用执行。 存储过程思想上很简单,就是数据库 SQL 语言层面的代码封装与重用。
CREATE PROCEDURE update_user_age(IN p_id INT, IN p_new_age INT) BEGIN START TRANSACTION; UPDATE users SET age = p_new_age WHERE id = p_id; INSERT INTO user_log (user_id, old_age, new_age, updated_at) VALUES (p_id, (SELECT age FROM users WHERE id = p_id), p_new_age, ...
mysql> DELIMITER $$ ;mysql> CREATE PROCEDURE job_data() > SELECT * FROM JOBS; $$ Query OK, 0 rows affected (0.00 sec) Explanation: - CREATE PROCEDURE command creates the stored procedure. - Next part is the procedure name. Here the procedure name is " job_data". ...
[RLogger] ERROR 1312: SELECT in a stored procedure must have INTO THIS IS THE ERROR I GET WHEN I EXECUTE YOUR MODIFIED CODE In Sybase/MS SQLSERVER, you can call PRINT syntax inside procs to print a variable. Is there a similar keywork available in mySQL. I checked the manual and it...