Converting rows into columns with dynamic heading - SQL Server 2008

Question

I have a set of data that appears as below:

PatientID   Custodian
17          Parent1
17          Parent2
18          Parent1
18          Parent2
18          Parent3
19          Parent1

I want output as:

PatientID    Custodian 1         Custodian 2         Custodian 3
17           Parent1             Parent2
18           Parent1             Parent2             Parent3
19           Parent1

Please help in writing SQL query for this.

Answer 1

You could use the PIVOT function, but you'd need to add a column with the matching Custodian ID. You COULD use some dynamic SQL for the 'custodian IN' section, but it could get messy. Something like this on the PIVOT:

CREATE TABLE #Temp
(
PatientID INT NOT NULL
,Custodian VARCHAR(10) NOT NULL
)

INSERT INTO #Temp
VALUES
(17,'Parent1')
,(17,'Parent2')
,(18,'Parent1')
,(18,'Parent2')
,(18,'Parent3')
,(19,'Parent1')

CREATE TABLE #Temp2
    (
    PatientID INT NOT NULL
    ,Parent VARCHAR(20) NOT NULL
    ,Custodian VARCHAR(20) NOT NULL
    )

INSERT INTO #Temp2
SELECT
    a.PatientID
    ,a.Custodian Parent
    ,'Custodian' + SUBSTRING(Custodian,7,10) Custodian
FROM #Temp a

SELECT *
FROM #Temp2 a (NOLOCK)
PIVOT (
    MAX(Parent)
    FOR Custodian IN ([Custodian1],[Custodian2],[Custodian3]))
    AS ParentID

DROP TABLE #Temp
DROP TABLE #Temp2