Clear out values from dropped columns during REPACK (CONCURRENTLY)
When repacking a table concurrently, some border conditions can cause
a concurrent update to propagate the original old tuple to the transient
table (such as a trigger that returns OLD). That's essentially just
wasted space, which REPACK is there to remove. Prevent that by setting
the isnull flag to true for any column cataloged as dropped in tuples
being "replayed" as concurrent updates.
Reported-by: Radim Marek <radim@boringsql.com>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Backpatch: 19
Discussion: https://postgr.es/m/CAJgoLkK2UBzB1J9buCsSUbjf7bOqz-o_0=CeiTruU789BhBw-Q@mail.gmail.com
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/e5d25959cf8761c7dbdd7cfbb91338e94a40e8e2
Modified Files
--------------
src/backend/commands/repack.c | 36 +++++++----
.../injection_points/expected/repack_dropped.out | 47 ++++++++++++++
src/test/modules/injection_points/meson.build | 1 +
.../injection_points/specs/repack_dropped.spec | 71 ++++++++++++++++++++++
4 files changed, 144 insertions(+), 11 deletions(-)
