Unpivot table with multiple columns and dynamic column names - sql

Question

I am trying to unpivot a table with multiple rows and columns. Each row needs to be extratced to 2 rows with specific columns and the column names need to be renamed and a new column needs to added based on the columns selected!
I am including before and after sample data and a script to setup the data.
CREATE TABLE #tmpProducts (
ProductId INT,
ProductName nVARCHAR(100),
B2B_GrossRevenue DECIMAL(10,2),
B2B_DirectCost DECIMAL(10,2),
B2B_NetRevenue DECIMAL(10,2),
B2C_GrossRevenue DECIMAL(10,2),
B2C_DirectCost DECIMAL(10,2),
B2C_NetRevenue DECIMAL(10,2)
)
INSERT INTO #tmpProducts SELECT 1, 'Product1',1545.00,406.25,1138.75,195.00,35.10,159.90
INSERT INTO #tmpProducts SELECT 2, 'Product2',902.00,189.00,713.00,3280.00,590.40,2689.60
INSERT INTO #tmpProducts SELECT 3, 'Product3',15665.00,3988.39,11676.61,6247.00,1124.46,5122.54
INSERT INTO #tmpProducts SELECT 4, 'Product4',736.00,196.16,539.84,2395.00,431.10,1963.90
SELECT * FROM #tmpProducts
DROP TABLE #tmpProducts
CREATE TABLE #tmpProducts2 (
ProductId INT,
ProductName nVARCHAR(100),
[Type] nVARCHAR(3),
GrossRevenue DECIMAL(10,2),
DirectCost DECIMAL(10,2),
NetRevenue DECIMAL(10,2)
)
INSERT INTO #tmpProducts2 SELECT 1, 'Product1','B2B',1545.00,406.25,1138.75
INSERT INTO #tmpProducts2 SELECT 1, 'Product1','B2C',195.00,35.10,159.90
INSERT INTO #tmpProducts2 SELECT 2, 'Product2','B2B',902.00,189.00,713.00
INSERT INTO #tmpProducts2 SELECT 2, 'Product2','B2C',3280.00,590.40,2689.60
INSERT INTO #tmpProducts2 SELECT 3, 'Product3','B2B',15665.00,3988.39,11676.61
INSERT INTO #tmpProducts2 SELECT 3, 'Product3','B2C',6247.00,1124.46,5122.54
INSERT INTO #tmpProducts2 SELECT 4, 'Product4','B2B',736.00,196.16,539.84
INSERT INTO #tmpProducts2 SELECT 4, 'Product4','B2C',2395.00,431.10,1963.90
SELECT * FROM #tmpProducts2
DROP TABLE #tmpProducts2
I have attempted this but i can't get past the second column and im not sure how at add a new column with specific text, (probably dynamic sql but trying to avoid this if possible)
Here is the start of my attempt, any help would be much appreciated.
SELECT ProductId, ProductName,GrossRevenue
FROM (
SELECT ProductId, ProductName, B2B_GrossRevenue,B2C_GrossRevenue FROM #tmpProducts
) as t
UNPIVOT ( GrossRevenue for test IN (B2B_GrossRevenue,B2C_GrossRevenue)) AS unpvt

Answer 1

You just keep unpivoting
SELECT ProductId,ProductName, Substring(col1,1,3) as type, GrossRevenue, DirectCost, NetRevenue
FROM (
SELECT * FROM #tmpProducts
) as t
UNPIVOT ( GrossRevenue for col1 IN (B2B_GrossRevenue,B2C_GrossRevenue)) AS unpvt
unpivot ( DirectCost for col2 in (B2b_DirectCost, B2c_DirectCost)) up2
unpivot ( NetRevenue for col3 in (B2b_NetRevenue, B2c_NetRevenue)) up3
where SUBSTRING(col1,1,3)=SUBSTRING(col2,1,3)
and SUBSTRING(col1,1,3)=SUBSTRING(col3,1,3)
and join on the col columns to filter out mismatches

Answer 2

Here is a way to do this using Dynamic SQL. This will allow you to get all of the columns upon execution. Then you will not have to alter the query if you get any data changes. This does both an UNPIVOT and PIVOT:
DECLARE #colsUnPivot AS NVARCHAR(MAX),
#colsPivot AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX)
SET #colsUnPivot = stuff((select ','+quotename(C.name)
from sys.columns as C
where C.object_id = object_id('tmpProducts') and
C.name like 'B2%'
for xml path('')), 1, 1, '')
SET #colsPivot = stuff((select DISTINCT ','+quotename(right((C.name), len(C.name)-4))
from sys.columns as C
where C.object_id = object_id('tmpProducts') and
C.name like 'B2%'
for xml path('')), 1, 1, '')
set #query
= ' SELECT ProductId, ProductName, [type], ' + #colsPivot +'
FROM
(
SELECT ProductId, ProductName, substring(field, 1, 3) [type]
, value, right((field), len(field)-4) as col
from tmpProducts
unpivot
(
value
for field in (' + #colsUnPivot + ')
) unpvt
) x
PIVOT
(
sum(value)
FOR col IN (' + #colsPivot +')
)p'
execute(#query)
See SQL Fiddle with Demo

Answer 3

If you have multiple groups that you're looking to pivot around you can also do something like this:
Select *
from table
unpivot include nulls ( (test_name, test_date) for col_nm in ( (test1, date1) as 'test_val1'
,(test2, date2) as 'test_val2'
,(test3, date3) as 'test_val3'
)
)