Comment by gorgoiler
Additionally, mutable fields will quite often benefit from having a separate edit table which records the old value, the new value, who changed it, and when. Your main table’s created and updated times can be a function of (or a complement to) the edit table.
It is tempting to supernormalize everything into the relations object(id, type) and edit(time, actor_id, object_id, key, value). This is getting dangerously and excitingly close to a graph database implemented in a relational database! Implement one at your peril — what you gain in schemaless freedom you also lose in terms of having the underlying database engine no longer enforcing consistency on your behalf.
> This is getting dangerously and excitingly close to a graph database implemented in a relational database!
This feels like a great unresolved tension in database / backend design - or maybe I'm just not sophisticated enough to notice the solutions?
Is the solution event sourcing and using the relational database as a "read model" only? Is that where the truly sophisticated application developers are at? Is it really overkill for everybody not working in finance? Or is there just not a framework that's made it super easy yet?
Users demand flexible schemas - should we tell them no?