One thing you could consider is a range type for your "versionTS" field instead of a single point in time.
So that would be: CREATE TABLE objects ( objectID uuid, versionID uuid, validRange tsrange, objectData text, ); See https://www.postgresql.org/docs/12.5/rangetypes.html for more information. In particular, you can enforce the obvious business rule, that there is no objectID with overlapping validRanges (as long as you have the btree_gist extension): CREATE EXTENSION btree_gist; CREATE TABLE objects ( objectID uuid, versionID uuid, validRange tsrange, objectData text, EXCLUDE USING GIST(objectID WITH =, validRange WITH &&) ); On Fri, May 28, 2021 at 8:20 PM Laura Smith < n5d9xq3ti233xiyif...@protonmail.ch> wrote: > Hi > > I was wondering what the current thinking is on ways to model versioning > in Postgres. > > The overall premise is that the latest version is the current version > unless a rollback has occurred, in which case versions get tracked from the > rollback point (forking ?). > > My initial naïve starting point is something along the lines of : > > create table objects ( > objectID uuid, > versionID uuid, > versionTS timestamp > objectData text > ); > > This obviously creates a fool-proof answer to "latest version is the > current version" because its a simple case of an "where objectID=x order by > versionTS desc limit 1" query. However it clearly doesn't cover the > rollback to prior scenarios. > > I then though about adding a simple "versionActive boolean". > > But the problem with that is it needs hand-holding somewhere because there > can only be one active version and so it would introduce the need for a > "active switch" script somewhere that activated the desired version and > deactivated the others. It also perhaps is not the right way to deal with > tracking of changes post-rollback. > > How have others approached the problem ? > > N.B. If it makes any difference, I'm dealing with a 12.5 install here, but > this could easily be pushed up to 13 if there are benefits. > > Thanks for your time. > > Laura > > >
