Dynamic Pivot Table across multiple columns - sql

Question

I'm a fairly new to SQL and could use some help. I have a table of time sheet data with a separate time sheet on each row. Each time sheet has a column with jobcode1 to jobcode16 that stores a string indicating a job code. Each of those has a corresponding TotalJob1 to TotalJob16.
I've managed to create a pivot on the JobCode1 no problem with a column for each Job and the total from TotalJob1. I used this to build it.
DECLARE #DynamicPivotQuery AS NVARCHAR(MAX)
DECLARE #ColumnName AS NVARCHAR(MAX)
SELECT #ColumnName = ISNULL(#ColumnName + ',','') + QUOTENAME(TS_Job1Code)
FROM (SELECT DISTINCT TS_Job1Code FROM
dbo.timesheetData) as timesheetdata
SET #DynamicPivotQuery =
N'SELECT VolumeID, ' + #ColumnName + '
FROM dbo.timesheetData
PIVOT(SUM(TS_TotalJob1)
FOR TS_Job1Code IN (' + #ColumnName + ')) AS PVTTable'
EXEC sp_executesql #DynamicPivotQuery
I'm struggling to iterate over the other Job columns and merge them into one big pivot table and was hoping someone might be able to give me a pointer?
My thought was to try and repeat the step 16 times but I don't think this is even close to the right way.
DECLARE #DynamicPivotQuery AS NVARCHAR(MAX)
DECLARE #ColumnName AS NVARCHAR(MAX)
DECLARE #N AS INT
DECLARE #NCHAR AS NVARCHAR(MAX)
SET #N = 1
WHILE #N < 17
BEGIN
SET #NCHAR = CAST(#N as VARCHAR)
SELECT #ColumnName = ISNULL(#ColumnName + ',','') + QUOTENAME(('TS_Job' +
#NCHAR + 'Code'))
FROM (SELECT DISTINCT ('TS_Job' + #NCHAR + 'Code') FROM
dbo.timesheetData) as timesheetdata
SET #DynamicPivotQuery =
N'SELECT ' + #ColumnName + '
FROM dbo.timesheetData
PIVOT(SUM(TS_TotalJob' + #NCHAR + ')
FOR TS_Job' + #NCHAR + 'Code IN (' + #ColumnName + ')) AS PVTTable'
EXEC sp_executesql #DynamicPivotQuery
SET #N = #N + 1
END
EXEC sp_executesql #SQL
Original
+-------------+----------+----------+----------+-----------+-----------+-----------+
| TimesheetID | JobCode1 | JobCode2 | JobCode3 | TotalJob1 | TotalJob2 | TotalJob3 |
+-------------+----------+----------+----------+-----------+-----------+-----------+
| 1 | J1 | J3 | | 10 | 9 | |
+-------------+----------+----------+----------+-----------+-----------+-----------+
| 2 | J2 | J1 | J3 | 5 | 5 | 5 |
+-------------+----------+----------+----------+-----------+-----------+-----------+
| 3 | J2 | | | 6 | 3 | 1 |
+-------------+----------+----------+----------+-----------+-----------+-----------+
What I want to achieve
+-------------+----+----+----+----+----+
| TimesheetID | J1 | J2 | J3 | J4 | J6 |
+-------------+----+----+----+----+----+
| 1 | 10 | | 9 | | |
+-------------+----+----+----+----+----+
| 2 | 5 | 5 | 5 | | |
+-------------+----+----+----+----+----+
| 3 | | 6 | | 3 | 1 |
+-------------+----+----+----+----+----+

Answer 1

It's going to get painfully complicated, but one thing you can do is to UNPIVOT your data so that it looks like this:
TimesheetId JobCode JobTotal
1 J1 10
1 J3 9
2 J1 5
....
And then PIVOT that derived table to get your desired result.

Answer 2

Like Tab mentioned, you can unpivot your data first and then Pivot it again.
You can use CROSS APPLY and VALUES to unpivot your table into a temp table.
SELECT ca.*
INTO #temp
FROM timesheet
CROSS APPLY (VALUES
(TimesheetID, JobCode1, TotalJob1),
(TimesheetID, JobCode2, TotalJob2),
(TimesheetID, JobCode3, TotalJob3)
) ca(TimesheetID, JobCode, TotalJob)
this gives you a table like
TimesheetID JobCode TotalJob
----------- ------- -----------
1 J1 10
1 J3 9
1 NULL NULL
2 J2 5
2 J1 5
2 J3 5
3 J2 6
3 NULL 3
3 NULL 1
not sure if you'd have null jobcodes in actual data.. but you can eliminate them using Where ca.JobCode IS NOT NULL above
Then you create your dynamic column string from the temp table
DECLARE #JobCodes nvarchar(MAX)
SELECT #JobCodes = COALESCE(#JobCodes + ',','') + QUOTENAME(JobCode)
FROM #temp
GROUP BY JobCode
ORDER BY JobCode
Then build your dynamic pivot. Instead of creating global temp table, just use the same query before in your pivot query.
DECLARE #Sql nvarchar(max)
SET #Sql = N'
SELECT TimeSheetID,' + #JobCodes
+ 'FROM (
SELECT ca.*
FROM timesheet
CROSS APPLY (VALUES
(TimesheetID, JobCode1, TotalJob1),
(TimesheetID, JobCode2, TotalJob2),
(TimesheetID, JobCode3, TotalJob3)
) ca(TimesheetID, JobCode, TotalJob)
) t
PIVOT (
SUM(TotalJob)
FOR JobCode IN (' + #JobCodes + ')
) p'
EXEC sp_executesql #Sql