MySQL存储过程

/*创建有输入输出参数的存储过程*/
DELIMITER $$
DROP PROCEDURE IF EXISTS `cosbuyer`.`pp`$$
CREATE 
  PROCEDURE `cosbuyer`.`pp`(IN a INT,IN b INT,OUT c INT)  
  BEGIN
	SET c=a+b;
	SELECT c;
  END$$
DELIMITER ;

CALL pp(10,20,@a);
SELECT @a;




/*创建有输入输出参数分页的存储过程*/
DELIMITER $$
DROP PROCEDURE IF EXISTS `cosbuyer`.`fenye`$$
CREATE 
  PROCEDURE `cosbuyer`.`fenye`(
  IN p_table_name VARCHAR(1024),
  IN p_fields VARCHAR(1024),
  IN p_page_size INT,
  IN p_page_now INT,
  IN p_order_string VARCHAR(128),
  IN p_where_string VARCHAR(1024),
  OUT p_out_rows INT)  
  NOT DETERMINISTIC
  SQL SECURITY DEFINER
  COMMENT '分页存储过程'
BEGIN
  /*定义变量*/
  DECLARE m_begin_row INT DEFAULT 0;
  DECLARE m_limit_string CHAR(64);
  /*构造语句*/
  SET m_begin_row = (p_page_now - 1)*p_page_size;
  SET m_limit_string = CONCAT(' limit ',m_begin_row,',',p_page_size);
  /*定义变量*/
  SET @COUNT_STRING = CONCAT('select count(*) into  @ROWS_TOTAL from ',p_table_name,' ',p_order_string);
  SET @MAIN_STRING = CONCAT('select ',p_fields,' from ',p_table_name,' ',p_where_string,' ',p_order_string,' ',m_limit_string);
   /*预处理*/
  PREPARE count_stmt FROM @COUNT_STRING;
  EXECUTE count_stmt;
  DEALLOCATE PREPARE count_stmt;
  SET p_out_rows = @ROWS_TOTAL;
  
  PREPARE main_stmt FROM @MAIN_STRING;
  EXECUTE main_stmt;
  DEALLOCATE PREPARE main_stmt;
  
  END$$
DELIMITER ;



CALL fenye( 'tb_pdt_product','id,pdtname,price',10,11,'order by id desc ',' ',@abc);
SELECT @abc;







说明:
declare v_name varchar(50) default 'abc';
set abc = 'singhoo';
set @name='singhoo';

@name与v_name的区别是:
它们的作用范围不一样@name是在会话过程起作用，它的作用是全局的，在存储过程之外也可以调用
v_name是在begin...end语句块内，只能在块中使用
而且@name要定义在最后，否则会出错