Column into rows and make a master table of columns - sql-server

Question

I need insert columns data to a different table and create master table for columns
Like example : I need to convert table tblcatData into two tables tblCat and tblcatDataNew
tblCatData
Primaykey | A | B | C | D | D | F | G | H | I | J | K | L | M |
--------------------------------------------------------------------
1 | 1 | 2 | 3 | 5 | 5 | 5 | 3 | 3 | 3 | 1 | 4 | 1 | 1 |
2 | 1 | 2 | 5 | 5 | 5 | 5 | 3 | 5 | 3 | 1 | 1 | 5 | 1 |
3 | 5 | 2 | 3 | 5 | 5 | 5 | 5 | 3 | 3 | 1 | 1 | 1 | 4 |
tblCat
PrimaryKey | Category
----------------------------
1 | A
2 | B
3 | C
4 | D
5 | E
6 | F
7 | G
. .
. .
. .
tblCatDataNew
PrimaryKey | FK_CatID | Data |
-----------------------------------
1 | 1 | 1 |
2 | 1 | 1 |
3 | 1 | 5 |
4 | 2 | 2 |
5 | 2 | 2 |
6 | 2 | 2 |
7 | 3 | 3 |
8 | 3 | 5 |
. . .
. . .
. . .

Answer 1

You could try the following scenario:
Create tblCat.
Create tblCatDataNew with the following deviations from the original design:
the FK_CatID column is allowed to accept NULLs temporarily (or maybe permanently, if that was your original intention);
an extra column is added temporarily to receive the category names from the original table.
Unpivot tblCatData and insert the results into tblCatDataNew (the values into Data and the column names, as category names, into the temporary column).
Select all the distinct category names from tblCatDataNew and insert them into tblCat. (That will produce the key values for them.)
Update the foreign keys in tblCatDataNew from tblCat, joining the two tables by category names.
Drop the temporary column from tblCatDataNew.
Set tblCatDataNew.FK_CatID as NOT NULL (that is, if you wanted it to be so).
Here's the entire test script, including creation of the original table (in case someone would like to try it):
BEGIN TRANSACTION
GO
/* prepare the original table, for tests */
WITH data (
Primaykey, A, B, C, D, E, F, G, H, I, J, K, L, M
) AS (
SELECT 1 , 1, 2, 3, 5, 5, 5, 3, 3, 3, 1, 4, 1, 1 UNION ALL
SELECT 2 , 1, 2, 5, 5, 5, 5, 3, 5, 3, 1, 1, 5, 1 UNION ALL
SELECT 3 , 5, 2, 3, 5, 5, 5, 5, 3, 3, 1, 1, 1, 4
)
SELECT * INTO tblCatData FROM data;
GO
/* Step 1 */
CREATE TABLE tblCat (
PrimaryKey int IDENTITY CONSTRAINT PK_tblCat PRIMARY KEY,
Category varchar(50) NOT NULL
);
GO
/* Step 2 */
CREATE TABLE tblCatDataNew (
PrimaryKey int IDENTITY CONSTRAINT PK_tblCatDataNew PRIMARY KEY,
FK_CatID int NULL CONSTRAINT FK_tblCatDataNew_tblCat FOREIGN KEY REFERENCES tblCat (PrimaryKey),
Data int,
Category varchar(50)
);
GO
/* Step 3 */
INSERT INTO tblCatDataNew (
Data,
Category
)
SELECT
Data,
Category
FROM tblCatData
UNPIVOT (
Data for Category IN (A, B, C, D, E, F, G, H, I, J, K, L, M)
) u
ORDER BY
Category,
Primaykey;
GO
/* Step 4 */
INSERT INTO tblCat (Category)
SELECT DISTINCT Category
FROM tblCatDataNew
GO
/* Step 5 */
UPDATE tblCatDataNew
SET FK_CatID = c.PrimaryKey
FROM tblCat c
WHERE tblCatDataNew.Category = c.Category
GO
/* Step 6 */
ALTER TABLE tblCatDataNew
DROP COLUMN Category
GO
/* Step 7 */
ALTER TABLE tblCatDataNew
ALTER COLUMN FK_CatID int NOT NULL
GO
/* view the results */
SELECT * FROM tblCat
SELECT * FROM tblCatDataNew
GO
ROLLBACK TRANSACTION
Note that the UNPIVOT clause is supported in SQL Server starting from the 2005 version. In earlier versions you'd have to use a different method to unpivot data (Step 3), e.g. like this:
INSERT INTO tblCatDataNew (
Data,
Category
)
SELECT
Data = CASE x.CatNum
WHEN 1 THEN A
WHEN 2 THEN B
WHEN 3 THEN C
WHEN 4 THEN D
WHEN 5 THEN E
WHEN 6 THEN F
WHEN 7 THEN G
WHEN 8 THEN H
WHEN 9 THEN I
WHEN 10 THEN J
WHEN 11 THEN K
WHEN 12 THEN L
WHEN 13 THEN M
END,
Category = CASE x.CatNum
WHEN 1 THEN 'A'
WHEN 2 THEN 'B'
WHEN 3 THEN 'C'
WHEN 4 THEN 'D'
WHEN 5 THEN 'E'
WHEN 6 THEN 'F'
WHEN 7 THEN 'G'
WHEN 8 THEN 'H'
WHEN 9 THEN 'I'
WHEN 10 THEN 'J'
WHEN 11 THEN 'K'
WHEN 12 THEN 'L'
WHEN 13 THEN 'M'
END
FROM tblCatData
CROSS JOIN (
SELECT 1 UNION ALL
SELECT 2 UNION ALL
SELECT 3 UNION ALL
SELECT 4 UNION ALL
SELECT 5 UNION ALL
SELECT 6 UNION ALL
SELECT 7 UNION ALL
SELECT 8 UNION ALL
SELECT 9 UNION ALL
SELECT 10 UNION ALL
SELECT 11 UNION ALL
SELECT 12 UNION ALL
SELECT 13
) x (CatNum)
ORDER BY
Category,
Primaykey;
or even like this:
INSERT INTO tblCatDataNew (
Data,
Category
)
SELECT
Data = CASE x.CatNum
WHEN 1 THEN A
WHEN 2 THEN B
WHEN 3 THEN C
WHEN 4 THEN D
WHEN 5 THEN E
WHEN 6 THEN F
WHEN 7 THEN G
WHEN 8 THEN H
WHEN 9 THEN I
WHEN 10 THEN J
WHEN 11 THEN K
WHEN 12 THEN L
WHEN 13 THEN M
END,
Category = x.CatName
FROM tblCatData
CROSS JOIN (
SELECT 1, 'A' UNION ALL
SELECT 2, 'B' UNION ALL
SELECT 3, 'C' UNION ALL
SELECT 4, 'D' UNION ALL
SELECT 5, 'E' UNION ALL
SELECT 6, 'F' UNION ALL
SELECT 7, 'G' UNION ALL
SELECT 8, 'H' UNION ALL
SELECT 9, 'I' UNION ALL
SELECT 10, 'J' UNION ALL
SELECT 11, 'K' UNION ALL
SELECT 12, 'L' UNION ALL
SELECT 13, 'M'
) x (CatNum, CatName)
ORDER BY
Category,
Primaykey;
Here are the results that the above script produced for me:
tblCat:
PrimaryKey Category
----------- --------------------------------------------------
1 A
2 B
3 C
4 D
5 E
6 F
7 G
8 H
9 I
10 J
11 K
12 L
13 M
tblCatDataNew:
PrimaryKey FK_CatID Data
----------- ----------- -----------
1 1 1
2 1 1
3 1 5
4 2 2
5 2 2
6 2 2
7 3 3
8 3 5
9 3 3
10 4 5
11 4 5
12 4 5
13 5 5
14 5 5
15 5 5
16 6 5
17 6 5
18 6 5
19 7 3
20 7 3
21 7 5
22 8 3
23 8 5
24 8 3
25 9 3
26 9 3
27 9 3
28 10 1
29 10 1
30 10 1
31 11 4
32 11 1
33 11 1
34 12 1
35 12 5
36 12 1
37 13 1
38 13 1
39 13 4

Answer 2

You can use union to unpivot the columns, and select ... into to store the result in a new table:
select PrimaryKey
, FK_CatId
, Category
into tblCatDataNew
from (
select PrimaryKey
, 1
, A
from tblCatData
union all
select PrimaryKey
, 2
, B
from tblCatData
union all
...
)