mysql存储过程 在动态SQL内获取返回值

MySql通用分页存储过程
 
 过程参数
 

p_cloumns varchar(500),p_tables varchar(100),p_where varchar(4000),p_order varchar(100),p_pageindex int,p_pagesize int,out p_recordcount int,out p_pagecount int
 
 $:begin
    declare v_sqlcounts varchar(4000);
    declare v_sqlselect varchar(4000);
 #拼接查询总记录的SQL语句
   set v_sqlcounts = concat('select count(*) into @recordcount from ',p_tables,p_where);
    #select v_sqlcounts;leave $;
   set @sqlcounts = v_sqlcounts;
   prepare stmt from @sqlcounts;
        execute stmt;
  deallocate prepare stmt;
   #获取动态SQL语句返回值
  set p_recordcount = @recordcount;
  #根据总记录跳数计算出总页数
   set p_pagecount = ceiling((p_recordcount+0.0)/p_pagesize);
   if p_pageindex <1 then
       set p_pageindex = 1;
     elseif p_pageindex > p_pagecount and p_pagecount <> 0 then
       set p_pageindex = p_pagecount;
   end if;
   #拼接分页查询记录的动态SQL语句
   set v_sqlselect = concat('select ',p_cloumns,' from ',p_tables,p_where,if(p_order is not null,p_order,''),' limit ',(p_pageindex-1)*p_pagesize,' , ',p_pagesize);
   #select v_sqlselect;leave $;
   set @sqlselect = v_sqlselect;
    prepare stmtselect from @sqlselect;
   execute stmtselect;
    deallocate prepare stmtselect;
   end $

Sql代码

1. #拼接查询总记录的SQL语句   
2. set v_sqlcounts = concat('select count(*) into @recordcount from ',v_tables,v_where);   
3. set @sqlcounts := v_sqlcounts;   
4. #预处理动态SQL   
5. prepare stmt from @sqlcounts;   
6. #传递动态SQL内参数   
7. set @s1= categoryid;   
8. execute stmt using @s1;   
9. deallocate prepare stmt;   
10. #获取动态SQL语句返回值   
11. set recordcount = @recordcount;  

#拼接查询总记录的SQL语句 set v_sqlcounts = concat('select count(*) into @recordcount from ',v_tables,v_where); set @sqlcounts := v_sqlcounts; #预处理动态SQL prepare stmt from @sqlcounts; #传递动态SQL内参数 set @s1= categoryid; execute stmt using @s1; deallocate prepare stmt; #获取动态SQL语句返回值 set recordcount = @recordcount;

 以上我上再做存储过程分页里用到动态SQL里将查询到的count记录条数通过变量@recordcount放到recordcount里面了。

mysql的IF ELSE和其他数据库的判断有点不一样，简单的判断语句如下。

Sql代码

1. #根据总记录跳数计算出总页数   
2. set pagecount = ceiling((recordcount+0.0)/pagesize);   
3. if pageindex <1 then  
4.     set pageindex = 1;   
5. elseif pageindex > pagecount then  
6.     set pageindex = pagecount;   
7. else  
8.     select pageindex,pagecount;   
9. end if;  

#根据总记录跳数计算出总页数 set pagecount = ceiling((recordcount+0.0)/pagesize); if pageindex <1 then set pageindex = 1; elseif pageindex > pagecount then set pageindex = pagecount; else select pageindex,pagecount; end if;