行数据列数据互换SQL例子

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[weatherreport]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[weatherreport]
GO

CREATE TABLE [dbo].[weatherreport] (
 [id] [int] IDENTITY (1, 1) NOT NULL ,
 [city] [varchar] (50) COLLATE Chinese_PRC_CI_AS NULL ,
 [reportdate] [datetime] NULL ,
 [temperature] [decimal](18, 1) NULL
) ON [PRIMARY]
GO

 

declare   @s   varchar(8000)  
   
  set   @s='select  reportdate '  
  select   @s=@s+',['+city+']=max(case city when '''+city+''' then temperature else 0 end)'  
  from   weatherreport    
  group   by   city    
  set   @s=@s+' from weatherreport group by reportdate'  
   
exec(@s)
select  reportdate ,[广州]=max(case city when '广州' then temperature else 0 end),
[阳光]=max(case city when '阳光' then temperature else 0 end),
[湛江]=max(case city when '湛江' then temperature else 0 end)
from weatherreport group by reportdate

select * from weatherreport

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[GetIDTableByIDList]') and xtype in (N'FN', N'IF', N'TF'))
drop function [dbo].[GetIDTableByIDList]
GO

SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS OFF
GO

 

CREATE FUNCTION GetIDTableByIDList( @IDList nvarchar(4000),@SPLITCHAR nvarchar(50))
returns @T  table(ID varchar(20))  
as  
begin
/*

declare @IDList nvarchar(4000)

set @IDList='canip,ok,l'
@SPLITCHAR nvarchar(50),
select * from dbo.IDTable(@IDList)
*/

declare @ID NVARCHAR(50)
if(@SPLITCHAR='')
set @SPLITCHAR=','
if(CHARINDEX(@SPLITCHAR,@IDList)>0)
begin
DECLARE @L INT -- 第一个分隔字符的位置
DECLARE @S INT -- 第二个分隔字符的位置
SET @L = 0
SET @S = CHARINDEX(@SPLITCHAR, @IDList, @L)
WHILE @L <= LEN(@IDList)
BEGIN
 IF @S = 0 SET @S = LEN(@IDList) + 1 -- 如果到最后一个字符串那么第二个分隔字符的位置就是这个字符串的长度加一
 SET @ID = SUBSTRING(@IDList, @L, @S - @L) -- 取值
 SET @L = @S + 1
 SET @S = CHARINDEX(@SPLITCHAR, @IDList, @L)
 IF LTRIM(RTRIM(@ID)) = '' CONTINUE -- 如果是空字符串就跳过
if(not exists(select [ID] from @T where [id]=@ID))
 insert into @T([ID])select @ID
--print @ID

End
end
else
insert into @T([ID])select @IDList
RETURN
END

 

 

 

GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO

 ----------------------------------------------

-- 功能: 将二进制字符串(VARCHAR)转换为十进制数(INT)
-- 输入参数: @StrBin 待转换的二进制字符串
-- 返回值: 相应的十进制数,如果二进制数非法,返回-1
-- 注意: @StrBin的长度不能大于31
-- 例子: SELECT dbo.Bin2Dec('1001') AS '15的二进制表示'
CREATE FUNCTION Bin2Dec(@StrBin VARCHAR(31))
RETURNS INT                        ---- 只支持最多31位长二进制字符串的解析
AS
BEGIN
    DECLARE @DecValue AS INT       -- 十进制值
    DECLARE @BinLen AS TINYINT     -- 二进制字符串长度
    DECLARE @Index AS TINYINT      -- 处理二进制字符串长度的索引
    DECLARE @CurrBit AS CHAR(1)    -- 当前在处理哪一位
    SET @BinLen = LEN(@StrBin)
    SET @DecValue = 0
    SET @Index = 0
    WHILE @Index < @BinLen
    BEGIN
        SET @Index = @Index + 1
        SET @CurrBit = CAST(SUBSTRING(@StrBin, @Index, 1) AS CHAR(1))
            IF (@CurrBit <> '0' AND @CurrBit <> '1')   -- 出现非法字符,返回-1  
            BEGIN
                SET @DecValue = -1
                BREAK
            END
        ELSE    
            BEGIN
SET @DecValue = @DecValue * 2
                IF(@CurrBit = '1')
                    BEGIN
                        SET @DecValue = @DecValue + POWER(2, 0)
                    END
            END     
    END
   
    RETURN @DecValue
END

 

 group by  with roll up /cube