InfoPath Dev

I have a form that has 3 repeating sections that are hidden and only shows up when the user mark a check box for each section.

The problem is that when 1 or 2 check boxes are marked, the user enter the data and hit the submit button. The remainder(s) section, wich is hidden, has a Null record that then is stored in my data base.

Is there a way I can prevent this?

Did you try adding default values to the fields that are hidden?

By default the 3 sections will be included with no-data

Click tools, form option, edit default values, then untick each of the repeating sections

The repeating sections will not be added to your database unless they are added while form is being filled in