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mysql儲存過程 在動態SQL內獲取返回值

MySql通用分頁儲存過程
過程引數
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);
 #拼接查詢總記錄的SQL語句
   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;
   #獲取動態SQL語句返回值
  set p_recordcount = @recordcount;
  #根據總記錄跳數計算出總頁數
   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;
   #拼接分頁查詢記錄的動態SQL語句
   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程式碼
  1. #拼接查詢總記錄的SQL語句   
  2. set v_sqlcounts = concat('select count(*) into @recordcount from ',v_tables,v_where);   
  3. set @sqlcounts := v_sqlcounts;   
  4. #預處理動態SQL   
  5. prepare stmt from @sqlcounts;   
  6. #傳遞動態SQL內參數   
  7. set @s1= categoryid;   
  8. execute stmt using @s1;   
  9. deallocateprepare stmt;   
  10. #獲取動態SQL語句返回值   
  11. set
     recordcount = @recordcount;  
#拼接查詢總記錄的SQL語句 set v_sqlcounts = concat('select count(*) into @recordcount from ',v_tables,v_where); set @sqlcounts := v_sqlcounts; #預處理動態SQL prepare stmt from @sqlcounts; #傳遞動態SQL內參數 set @s1= categoryid; execute stmt using @s1; deallocate prepare stmt; #獲取動態SQL語句返回值 set recordcount = @recordcount;

 以上我上再做儲存過程分頁裡用到動態SQL裡將查詢到的count記錄條數通過變數@recordcount放到recordcount裡面了。

mysql的IF ELSE和其他資料庫的判斷有點不一樣,簡單的判斷語句如下。

Sql程式碼
  1. #根據總記錄跳數計算出總頁數   
  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;  
#根據總記錄跳數計算出總頁數 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;