SQL Pivot Tables - Copy Excel Functionality - tsql

Question

Let's say I have a table like this:
Task Type Variable Hours Duration
One A X 10 5
One A Y 40 15
One B X 100 29
Two A X 5 2
Two B X 15 9
Two A Y 60 17
Three A Y 18 5
Where the combination of task-type-variable makes each row unique.
How can I get a pivot table like the following:
X Y
One A Hours 10 40
Duration 5 15
One B Hours 100 0
Duration 29 0
Two A Hours 5 60
Duration 2 17
Two B Hours 15 0
Duration 9 0
Three A Hours 0 18
Duration 0 5
Is this even possible in SQL? I know Excel can do this.

Answer 1

This is a really an UNPIVOT and a PIVOT. The following code achieves the desired results in a single query.
DECLARE #t TABLE (
Task varchar(5),
Type char(1),
Variable char(1),
Hours int,
Duration int
)
INSERT INTO #t
VALUES
('One', 'A', 'X', 10, 5),
('One', 'A', 'Y', 40, 15),
('One', 'B', 'X', 100, 29),
('Two', 'A', 'X', 5, 2),
('Two', 'B', 'X', 15, 9),
('Two', 'A', 'Y', 60, 17),
('Three', 'A', 'Y', 18, 5)
SELECT
P.Task,
P.Type,
CAST(P.Property AS varchar(8)) AS Property,
COALESCE(P.X, 0) AS X,
COALESCE(P.Y, 0) AS Y
FROM #t AS T
UNPIVOT (
Value FOR Property IN (
Hours,
Duration
)
) AS U
PIVOT (
SUM(Value) FOR Variable IN (
X,
Y
)
) AS P
This yields the following results.
Task Type Property X Y
----- ---- -------- ----------- -----------
One A Duration 5 15
One A Hours 10 40
One B Duration 29 0
One B Hours 100 0
Three A Duration 0 5
Three A Hours 0 18
Two A Duration 2 17
Two A Hours 5 60
Two B Duration 9 0
Two B Hours 15 0
As you can see, the Hours and Duration are flipped. I don't think there is any way to force an order using PIVOT alone. This could easily be remedied by joining to another table with the Property value with an associated sort order, as long as you had some other way to ensure the other columns sorted correctly first.