Hi,
I'm reading about MVCC here:
https://www.postgresql.org/docs/current/static/mvcc.html
<https://www.postgresql.org/docs/current/static/mvcc.html>.
In some cases I can use these transaction isolation modes, but in other cases,
I may want to manage the versions and concurrency manually. Is there a way to
select the “version” of a row, or is that data hidden to ordinary SQL
statements?
I’m thinking about a sequence of actions, which are logically a transaction,
but start on one thread and complete later on another thread. I don’t think I
can tie up a JDBC database connection for that long. I can add a `version
bigint` column to my table, and the final update will look like:
update ... where id = ? and version =
the_version_selected_earlier_in_a_different_thread
… and if that gets 0 rows, it can handle the conflict.
Rob
