Adding new fields on list page grid using new data source

Adding new fields on a positions list page grid in payroll module and these fields were coming from a new custom table. The steps are simple with one tricky part:

1. Create new table, define proper relations with other tables.

2. Add the table in the query used on the list page.

3. This is a tricky part: When you come back to list page and try to restore the form you will not be able to see the new data source. To do this right click on the data source node and again define the name of the query. This will reload the new structure from the query.

4. Then you can view the data source which you added in the query and then can drag the fields in the grid.