I want to collect data from three related tables in one application.

I can sum up data from a second-level table.

But I can't sum up the data from the third-level table.

I think the solution should be very simple, I just don't see it.

Hi @Serg-c0c6,

Thanks for your post and screenshot! I can help you with this -

The reason why your formula was not working is that there is no C_payments value or rowlink in the Clients table to pull data from. However, I have another way that may work better for you.

I re-created your data model and made some tweaks to meet your goals of calculating the sum for all payments for contracts of a given client. This is how I set it up:

I added another column to the Contracts table that calculates the sum of each contract:

I then added a couple of columns to the Client table that each calculate your desired sums.

The sum of the contracts is set up like this:

And here is how the sum of the payments is set up:

After this is set up in the Tables, you can simplify your formulas to pull the SUM data in the app.

For example, your contracts sum could look something like: `=$[ClientF][SUM Contracts]`

And your payments sum: `=$[ClientF][SUM Payments]`

Hope this helps! Let me know if you have any further questions on this