SQL選擇查詢轉換第一列為標題，第二列為行？

Question

是否可以將第一列轉換為標題，將第二列轉換為行？ 請在下面找到一個例子

   Type  | qty  (Header)
  Apple    4
  Orange   10
  Grapes   5


Apple | Orange | Grapes (Header)
4       10         5       

Answer 1

在SQL Server中，存在STUFF（）和EXEC（）函數以進行相同的動態查詢。

select @script = STUFF( SELECT qty + ' AS ' + type + ', ' from table_orig);

EXEC (@script);

在MySql中，可以使用EXECUTE：

SET @sqltxt = null;
SELECT GROUP_CONCAT(CONCAT( qty, ' AS ', type, ' ') ) INTO @sqltxt
FROM table_orig;

SET @sqltxt = concat('SELECT ', @sqltxt , ' FROM DUAL');

PREPARE stmt FROM @sqltxt;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

祝好運，

Answer 2

-只是一些樣品

create table #fruits ([type] varchar(10), quantity int)
insert into #fruits select  'Apple',4 union all select 'Orange', 10 union all select 'Grapes', 5

-首先獲得唯一的[結果]集

declare @sqlStr varchar(max)

select @sqlStr = '['+ 
replace(
stuff((select distinct ','+[type] as [text()]
from #fruits s
    for xml path ('')) ,1,1,'')
    ,',','],[') + ']' 
from #fruits s1

select @sqlStr

-組裝動態查詢

declare @sqlStr1 varchar(max)
set @sqlStr1 = 'select *
from #fruits  a
pivot (sum (quantity) for [type] in ('+@sqlStr+')
    ) p'

-運行動態查詢

 exec (@sqlStr1)    

希望這可以幫助

創建永久表的附加

declare @sqlStr1 varchar(max)
set @sqlStr1 = 'IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N''[dbo].[TblFruits]'') AND type in (N''U''))
DROP TABLE [dbo].[TblFruits]

select *
into TblFruits
from #fruits a
pivot (sum (quantity) for [type] in ('+@sqlStr+')
        ) p'

-- run dynamic query
 exec (@sqlStr1)