mysql 变量用法

-- 定义用户定义变量
SET @myVariable = 'Hello, World!';

-- 使用用户定义变量
SELECT @myVariable;

-- 定义局部变量
DELIMITER //
CREATE PROCEDURE myProcedure()
BEGIN
  DECLARE localVariable VARCHAR(255);
  SET localVariable = 'Hello from procedure!';
  SELECT localVariable;
END //
DELIMITER ;

-- 调用存储过程
CALL myProcedure();

-- 使用会话变量
SET @@global.time_zone = '+8:00';
SELECT @@session.time_zone;

SET @myVariable = 'Value';
SELECT @myVariable;

DELIMITER //
CREATE PROCEDURE myProcedure()
BEGIN
  DECLARE localVariable VARCHAR(255);
  SET localVariable = 'Hello from procedure!';
  SELECT localVariable;
END //
DELIMITER ;

SET @myCustomVariable = 'Value';
SELECT @myCustomVariable;