SQL Server 2005 - Pivoting Data without a sum / co

问题:

Sorry if this is covered elsewhere in another question, but I can't find any examples which exactly match what I need and I'm getting confused.

I have data in the table like this :-

Name   |   Value
---------------
John   |   Dog
John   |   Cat
John   |   Fish
Bob    |   Python
Bob    |   Camel

And I would like the data like this....

Name   |  Value_1 | Value_2 | Value_3
-------------------------------------
John   |  Dog     |  Cat    | Fish
Bob    |  Python  |  Camel  | NULL

I don't want to use case statements because the dog, cat, fish etc there are 20+ possible values and they could change overtime.

Anyone got any pointers?

回答1:

This comes close to what you're after. i've also included a table creation script and sample data for others to use. Inspiration for this solution came from here

-- Dynamic PIVOT
DECLARE @T AS TABLE(y INT NOT NULL PRIMARY KEY);

DECLARE
@cols AS NVARCHAR(MAX),
@y    AS INT,
@sql  AS NVARCHAR(MAX);

-- Construct the column list for the IN clause
-- e.g., [Dog],[Python]
SET @cols = STUFF(
(SELECT N',' + QUOTENAME(y) AS [text()]
FROM (SELECT DISTINCT [Value] AS y FROM dbo.table_1) AS Y
ORDER BY y
FOR XML PATH('')),
1, 1, N'');

-- Construct the full T-SQL statement
-- and execute dynamically
SET @sql = N'SELECT *
FROM (SELECT *
FROM dbo.table_1) AS D
PIVOT(MIN(value) FOR value IN(' + @cols + N')) AS P;';

PRINT @sql
EXEC sp_executesql @sql;
GO

Table creation:

CREATE TABLE [dbo].[Table_1](
    [Name] [varchar](50) COLLATE Latin1_General_CI_AS NULL,
    [Value] [varchar](50) COLLATE Latin1_General_CI_AS NULL
) ON [PRIMARY]

GO

Sample data:

insert into dbo.table_1 values ('John','Dog')
insert into dbo.table_1 values ('John','Cat')
insert into dbo.table_1 values ('John','Fish')
insert into dbo.table_1 values ('Bob ','Python')
insert into dbo.table_1 values ('Bob ','Camel')

回答2:

This question is somewhat similar:

Cross Tab - Storing different dates (Meeting1, Meeting2, Meeting 3 etc) in the same column

回答3:

Take a look at this :

http://dotnetgalactics.wordpress.com/2009/10/23/using-sql-server-20052008-pivot-on-unknown-number-of-columns-dynamic-pivot/

Might be helpful ..