Question

我有这样的查询结果：

Date       User1 User2 User3 ....
----------------------------------
1/1/2000   55     78    98   ...
1/1/2001   26     33    56   ...
1/1/2002   88     67    12   ...

列数未知，因为它是透视查询的结果。

我想将列的名称更改为如下所示：

Date    User1 (blue)  User2 (green)  User3(brown)

颜色是我从另一个表中检索的信息。

我怎样才能做到这一点？

由于

编辑：这是查询。

  DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT distinct ',' + QUOTENAME(C.Name)  
                    from [History]



            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')
set @query = 'SELECT [Date],' + @cols +' 
             from 
             (
                select [Date], Name, Value
                from [History]


             ) x
            pivot 
            (
                max(value)
                for Name in (' + @cols + ')
            ) p '

execute(@query)

Answer 1

SQL Fiddle

架构设置：

create table history (date datetime, name varchar(10), value int);
insert history values
 ('20130101', 'user1', 123),
 ('20130101', 'user2', 124),
 ('20130101', 'user3', 125),
 ('20130102', 'user1', 223),
 ('20130102', 'user3', 223),
 ('20130103', 'user2', 323);

create table colours (name varchar(10), colour_name varchar(10));
insert colours values
 ('user1', 'blue'),
 ('user2', 'green'),
 ('user3', 'brown');

<强>查询：

DECLARE @scols nvarchar(max),
        @cols AS NVARCHAR(MAX),
        @query AS NVARCHAR(MAX);

select @cols = STUFF((
  SELECT ',' + QUOTENAME(C.Name)  
  from (select distinct name from [History]) C
  ORDER BY C.Name
  FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,'');

select @scols = STUFF((
  SELECT ',' + QUOTENAME(Name) + ' AS ' + QUOTENAME(colour_Name)  
  from (select distinct c.name, x.colour_name
        from [History] C
        JOIN colours x on x.name = c.name) y
  ORDER BY Name
  FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,'');

set @query = '
    SELECT [Date],' + @scols +' 
    from (
        select [Date], Name, Value
        from [History]
         ) x
    pivot 
         (
        max(value)
        for Name in (' + @cols + ')
         ) p ';

-- print @query --<< uncomment this line to see the query that gets generated
exec (@query);

<强> Results ：

|                           DATE |   BLUE |  GREEN |  BROWN |
-------------------------------------------------------------
| January, 01 2013 00:00:00+0000 |    123 |    124 |    125 |
| January, 02 2013 00:00:00+0000 |    223 | (null) |    223 |
| January, 03 2013 00:00:00+0000 | (null) |    323 | (null) |

Answer 2

select Date, User1 as blue,User2 as green,User3 as brown from tableName

使用这样的查询。

使用“as”关键字更改列名。

Answer 3

获取映射您可以将旧列名称的查找表用于新列名称，例如

CREATE TABLE colname(
  oldname varchar(20),
  newname varchar(20)
)

insert into colname values ( 'user1','user1 (blue)');
insert into colname values ( 'user2','user2 (green)');

然后你可以构建一个使用这个映射的sql语句

declare @sq varchar(2000)
set @sq ='select date'
select @sq = @sq +  ',' + oldname + ' as [' + newname +']' from colname
set @sq = @sq + 'from ( existing query goes here ) ' 
select @sq

当@sq中的sql看起来很好时，你可以用

替换最后一个选择

exec ( @sq )

运行查询

在sql中动态更改列名称

3 个答案: