Add column to datatable and populate with query against same datatable in vb.net

Question

I have a datatable with five columns. I want to create a new column that contains the difference between two datetime fields for all rows.

The datatable, dtb, was originally populated from a sql server database. Current columns are: ID, startDate, codeID, Param, and endTime. The new column will be a duration that is the difference between endTime and startDate. The difference should be down to less than seconds, so if this can be done through sql I assume datediff with milliseconds parameter.

Answer 1

select ID, startDate, codeID, Param, endTime, DateDiff(ms,endTime,startDate) As yourdiff from dtb that will be your query. Do you want to alter the table?