How do i transform rows into columns in sql server 2005
There is a question here in stackoverflow with the same title but that is not what I am looking for.
I have a table like the one belowName | Count
----------------
Chery | 257
Drew | 1500
Morgon | 13
Kath | 500
Kirk | 200
Matt | 76
I need to trasform this result set into something like this
Chery | Drew | Morgon | Kath | Kirk | Matt
-------------------------------------------
257 1500 13 500 200 76
How do i acheive this usi开发者_StackOverflowng sql server 2005?
There are similar questions here,here answered in stackoverflow.
You need to use the operator PIVOT in your query to acheive this.Here is the example and explanation on how you can do that.The example is referenced from this source.
---I assumed your tablename as TESTTABLE---
DECLARE @cols NVARCHAR(2000)
DECLARE @query NVARCHAR(4000)
SELECT @cols = STUFF(( SELECT DISTINCT TOP 100 PERCENT
'],[' + t.Name
FROM TESTTABLE AS t
ORDER BY '],[' + t.Name
FOR XML PATH('')
), 1, 2, '') + ']'
SET @query = N'SELECT '+ @cols +' FROM
(SELECT t1.Name , t1.Count FROM TESTTABLE AS t1) p
PIVOT (MAX([Count]) FOR Name IN ( '+ @cols +' ))
AS pvt;'
EXECUTE(@query)
Explanation
1.The first part of the query
SELECT @cols = STUFF(( SELECT DISTINCT TOP 100 PERCENT
'],[' + t.Name
FROM TESTTABLE AS t
ORDER BY '],[' + t.Name
FOR XML PATH('')
), 1, 2, '') + ']'
gives you a nice flattened result of your Name column values in a single row as follow
[Cheryl],[Drew],[Karen],[Kath],[Kirk],[Matt]
You can learn more about the STUFF and XML PATH here and here.
2.SELECT + @cols + FROM
will select all the rows as coloumn names for the final result set (pvt - step 3)
i.e
Select [Chery],[Drew],[Morgan],[Kath],[Kirk],[Matt]
3.This query pulls all the rows of data that we need to create the cross-tab results. The (p) after the query is creating a temporary table of the results that can then be used to satisfy the query for step 1.
(SELECT t1.Name, t1.Count FROM TESTTABLE AS t1) p
4.The PIVOT expression
PIVOT (MAX (Count) FOR Name IN ( @cols) AS pvt
does the actual summarization and puts the results into a temporary table called pvt as
Chery | Drew | Morgon | Kath | Kirk | Matt
-------------------------------------------
257 1500 13 500 200 76
See Using PIVOT and UNPIVOT.
You can use the
PIVOT
andUNPIVOT
relational operators to change a table-valued expression into another table.PIVOT
rotates a table-valued expression by turning the unique values from one column in the expression into multiple columns in the output, and performs aggregations where they are required on any remaining column values that are wanted in the final output.UNPIVOT
performs the opposite operation to PIVOT by rotating columns of a table-valued expression into column values.
The quick answer is
SELECT Chery, Drew, Morgon, Kath, Kirk, Matt
FROM
(SELECT [Name], [Count] From Foo)
PIVOT
(
MIN([Count])
FOR [Name] IN (Chery, Drew, Morgon, Kath, Kirk, Matt)
) AS PivotTable
If you want to avoid anything complicated like a pivot or the accepted answer, you can do this! (most of the code is just setting up the test data just in case anyone wants to try it)
/* set up your test table */
declare @TestData table (Name Varchar(80),[Count] int)
insert into @TestData (Name, [count])
Select 'Chery' as name, 257 as [count]
union all select 'Drew', 1500
union all select 'Morgon',13
union all select 'Kath', 500
union all select 'Kirk', 200
union all select 'Matt', 76
/* the query */
Declare @Query Varchar(max)
Select @Query=Coalesce(@query+', ','SELECT ') +Convert(VarChar(5),[count]) +' as ['+name+']'
from @TestData
Execute (@Query)
/* result
Chery Drew Morgon Kath Kirk Matt
----------- ----------- ----------- ----------- ----------- -----------
257 1500 13 500 200 76
*/
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