On Fri, Apr 30, 2021 at 2:13 PM Jeff Davis <pg...@j-davis.com> wrote: > FWIW, this is not a problem in my table AM. I am fine having different > TIDs for each version, just like heapam.
This means that we are largely in agreement about the general nature of the problem. That seems like a good basis to redefine TID-like identifiers so that they can accommodate what you want to do. > For index-organized tables it does seem like an interesting problem. I strongly suspect that index-organized tables (or indirect indexes, or anything else that assumes that TID-like identifiers map directly to logical rows as opposed to physical versions) are going to break too many assumptions to ever be tractable. Assuming I have that right, it would advance the discussion if we could all agree on that being a non-goal for the tableam interface in general. This would allow us to clearly discuss how to solve the remaining problem of accommodating column stores and suchlike. That seems hard, but much more tractable. The fact that the tableam has almost no non-goals has always bothered me a bit. Especially on this particular point about purely logical TID-like identifiers. -- Peter Geoghegan