How can I transpose multiple unrelated columns into rows in SQL Server?

Question

I have a table that looks like the following:
PersonId   EyeColor    HairColor    FavoriteTVShow      FavoriteMovie    FavoriteFood    BirthInfo
---------- ----------- ------------ ------------------- ---------------- --------------- ------------------
A123       Brown       Black        The Price Is Right  NULL             Pizza           New York City
A444       NULL        Brown        Friends             Elf              Steak           Seattle

My desired result set is this:
PersonId ColorInfo FavoriteInfo       BirthInfo
-------- --------- ------------------ -------------
A123     Brown     The Price Is Right New York City
A123     Black     Pizza              NULL
A444     Brown     Friends            Seattle
A444     NULL      Elf                NULL
A444     NULL      Steak              NULL

So for each PersonId, each group of columns (2 ColorInfo cols, 3 FavoriteInfo cols, and 1 BirthInfo col) is transposed into rows. I've tried variations of CROSS APPLY and UNPIVOT, but I can't seem to get it just right. I know it's a weird request, but can anyone think of a good way to do this?
Thank you in advance!
Here's the T-SQL:
--Create the table
CREATE TABLE #test (
PersonId VARCHAR(10),
EyeColor VARCHAR(20),
HairColor VARCHAR(20),
FavoriteTVShow VARCHAR(30),
FavoriteMovie VARCHAR(30),
FavoriteFood VARCHAR(30),
BirthInfo VARCHAR(30)
)

--Populate the table
INSERT INTO #test
VALUES
('A123', 'Brown', 'Black', 'The Price Is Right', NULL, 'Pizza', 'New York City'),
('A444', NULL, 'Brown', 'Friends', 'Elf', 'Steak', 'Seattle')

--See the original result set.
SELECT *
FROM #test

--My desired result set
SELECT *
FROM ( VALUES ('A123', 'Brown', 'The Price Is Right', 'New York City'),
              ('A123', 'Black', 'Pizza', NULL),
              ('A444', 'Brown', 'Friends', 'Seattle'),
              ('A444', NULL, 'Elf', NULL),
              ('A444', NULL, 'Steak', NULL) ) t (PersonId, ColorInfo, FavoriteInfo, BirthInfo)

Jonathan Fite · Accepted Answer

I think that this will give you what you are looking for.  You have to hop through a few CTE's to unpivot the data, then add some attribute information and then pivot it back, but the output does match what you provided...
I had to add a CTE_RawData to convert everything to the same data type since the unpivot doesn't like mismatches...
DROP TABLE IF EXISTS #test

--Create the table
CREATE TABLE #test (
PersonId VARCHAR(10),
EyeColor VARCHAR(20),
HairColor VARCHAR(20),
FavoriteTVShow VARCHAR(30),
FavoriteMovie VARCHAR(30),
FavoriteFood VARCHAR(30),
BirthInfo VARCHAR(30)
)

--Populate the table
INSERT INTO #test
VALUES
('A123', 'Brown', 'Black', 'The Price Is Right', NULL, 'Pizza', 'New York City'),
('A444', NULL, 'Brown', 'Friends', 'Elf', 'Steak', 'Seattle')

;WITH CTE_RawData AS
    (
    SELECT PersonID 
        , CONVERT(NVARCHAR(30), EyeColor) AS EyeColor
        , CONVERT(NVARCHAR(30), HairColor) AS HairColor
        , CONVERT(NVARCHAR(30), FavoriteTVShow) AS FavoriteTVShow
        , CONVERT(NVARCHAR(30), FavoriteMovie) AS FavoriteMovie
        , CONVERT(NVARCHAR(30), FavoriteFood) AS FavoriteFood
        , CONVERT(NVARCHAR(30), BirthInfo) AS BirthInfo
    FROM #Test AS T
    )
, CTE_UP AS
    (
    SELECT PersonID 
        , Attribute 
        , [Value]
    FROM CTE_RawData AS T
        UNPIVOT ([Value] FOR Attribute IN (EyeColor, HairColor, FavoriteTVShow, FavoriteMovie, FavoriteFood, BirthInfo)) AS unpvt
    )
, CTE_UPRN AS
    (
    SELECT PersonID 
        --, Attribute 
        , [Value]
        , AttributeCategory = CASE  WHEN Attribute IN ('EyeColor', 'HairColor') THEN 'ColorInfo'
                                                                WHEN Attribute IN ('FavoriteTVShow', 'FavoriteMovie', 'FavoriteFood') THEN 'FavoriteInfo'
                                                                WHEN Attribute IN ('BirthInfo') THEN 'BirthInfo'
                                                                ELSE Attribute
                                                                END
        , RN = ROW_NUMBER() OVER (PARTITION BY PersonID, CASE   WHEN Attribute IN ('EyeColor', 'HairColor') THEN 'ColorInfo'
                                                                WHEN Attribute IN ('FavoriteTVShow', 'FavoriteMovie', 'FavoriteFood') THEN 'FavoriteInfo'
                                                                WHEN Attribute IN ('BirthInfo') THEN 'BirthInfo'
                                                                ELSE Attribute
                                                                END
                                    ORDER BY PersonID)
    FROM CTE_UP AS U
    )
SELECT PersonID 
    , RN 
    , ColorInfo 
    , FavoriteInfo 
    , BirthInfo 
FROM CTE_UPRN AS U
    PIVOT (MAX([Value]) FOR AttributeCategory IN (ColorInfo, FavoriteInfo, BirthInfo)) AS pvt
ORDER BY PersonID 
    , RN

How can I transpose multiple unrelated columns into rows in SQL Server?

One Answer

Add your own answers!

Ask a Question