msql 分页存储过程

mysql的分页存储过程，前台可以通过相应参数直接调用获取结果，也可以结合jqGrid的列表和分页器配置参数匹配使用

-- --------------------------------------------------------------------------------
-- Routine DDL
-- Note: comments before and after the routine body will not be stored by the server
-- --------------------------------------------------------------------------------
DELIMITER $$

CREATE DEFINER=`root`@`%` PROCEDURE `fenye`(
    IN p_table_name    VARCHAR(100),--表名    
    IN p_fields        VARCHAR(500),--所选字段 
    IN p_where_string  VARCHAR(500),--带where的过滤条件 
    IN p_order_string  VARCHAR(500),--带order的排序方式
    IN p_page_now      INT,    　　　--现在所在页数　
    IN p_page_size     INT,　　　　　 --每页的数量
    OUT p_out_rows     INT  　　　　  --输出参数，共计记录数量
)
BEGIN
     /*定义变量*/
    DECLARE m_begin_row INT DEFAULT 0;
    DECLARE m_limit_string VARCHAR(128);
    /*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);
    
    SET @COUNT_STRING = CONCAT('SELECT COUNT(*) INTO @ROWS_TOTAL FROM ', p_table_name, ' ', p_where_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