technollygy Member

Thanks for that. Yes, that's ok. I'm fine with that. On a related note, when I do need to replace null values with 0, I currently have to convert the column type to text, replace null with 0, then convert it back to integer. I'm sure there must be a more sensible way. Any ideas?

All it was is that I didn't realise that you could select two columns as the grouping! Thanks - I just needed someone to make it really obvious. For the benefit of anyone else: Resulting in...