On Sat, Aug 22, 2026 at 3:29 AM Jochen Bandhauer <jb(at)jbitc(dot)de> wrote:
> while using repack (concurrently) I found a behavior that I didn't
> expect. When running a "repack (concurrently) t;" in one session,
> another session with "transaction isolation level repeatable read"
> reports sometimes 0 for "select count(*) from t;".
This is a documented behavior; "repack concurrently" is allowed to
violate MVCC. There's a warning box about this in the docs for the
repack command [1], which notes "REPACK with the CONCURRENTLY option
is not MVCC-safe, see Section 13.6 for details".
[1] https://www.postgresql.org/docs/devel/sql-repack.html
--
Peter Geoghegan