mysql下的分页存储过程

CREATE PROCEDURE pro_page(
 in _sql varchar(1000),
 in _order varchar(1000),
 in _pagecurrent int,
 in _pagesize int
)
BEGIN
 if _pagesize<=1 then
  set _pagesize=20;
 end if;
 if _pagecurrent < 1 then
  set _pagecurrent = 1;
 end if;
 set @strsql = concat(_sql,' ',_order,' limit ',_pagecurrent*_pagesize-_pagesize,',',_pagesize);
 prepare stmtsql from @strsql;
 execute stmtsql;
 deallocate prepare stmtsql; 
END;