Konstantin Knizhnik schrieb am 05.07.2020 um 19:31:
I am surprised that you are saying you didn't feel big interest. My
reading of the thread is the opposite, that there was quite some
interest, but that there are technical challenges to overcome. So you
gave up on that work?
No, I have not gave up.
But...
There are well known problems of proposed approach:
1. Not supporting schema changes
2. Not compatible with DROP/TRUNCATE
3. Presence of large number of aborted transaction can slow down data access.
4. Semantic of join of tables with different timestamp is obscure.
Oracle partially solved this (at least 1,3 and 4 - don't know about 3) by storing the old
versions in a separate table that is automatically managed if you enable the feature. If
a query uses the AS OF to go "back in time", it's rewritten to access the
history table.
Thomas
