adding rows to dataset table manually after retrieving from DB

[Wokawidget]

I return a dataset from a function.
This has 3 fields.

Month, WorkHrs, ContractWrkHrs

So the data may look like:

1, 45, 234
3, 23, 98
11, 19, 101

So, the months are January, March and Novemeber.
before I pass this data to a datagrid to bind I would like to add all the other months. so the data in the dataset will be:

1, 45, 234
2, 0, 0
3, 23, 98
4, 0, 0
5, 0, 0
6, 0, 0
etc

How would I do this?
I basically want to show Jan to Dec in a grid whether they exist or not in the DB.

Woka