One option would be to use custom coded workflow actions. These are included with Operations Hub Professional/Enterprise. They allow you to write your own bespoke logic in either Javascript or Python within a workflow. You could do something like this to achieve your goal:
The only thing I would be mindful of is that HubDB has a hard limit of 10,000 rows. So depending on the number of deals you have it may be problematic. Also, if you don't mind me asking what is the reason you want to store deals in HubDB?
Our main HubDB has no more than 2000 rows, so that's a good idea, thanks. I'll have to read up on it though as I'm not familiar with the code that's needed.
Regarding HubDB using deal data, it's just the way that my employer originally set it up. We don't hold any of our customer data inside HubDB, but the customer information is associated with a unique row inside Deals (regarding sale / build status on our house plots) which in turn is cloned with HubDB so that I can create custom web modules from it.
I've started using custom objects for web modules but I'm limited to 100 rows on each call with a max of 10 calls hence the reason why I need to stick with HubDB for now.
One option would be to use custom coded workflow actions. These are included with Operations Hub Professional/Enterprise. They allow you to write your own bespoke logic in either Javascript or Python within a workflow. You could do something like this to achieve your goal:
The only thing I would be mindful of is that HubDB has a hard limit of 10,000 rows. So depending on the number of deals you have it may be problematic. Also, if you don't mind me asking what is the reason you want to store deals in HubDB?