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postgresql/src/include/access
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Alexander Korotkov 87985cc925 Allow locking updated tuples in tuple_update() and tuple_delete() 
Currently, in read committed transaction isolation mode (default), we have the
following sequence of actions when tuple_update()/tuple_delete() finds
the tuple updated by the concurrent transaction.

1. Attempt to update/delete tuple with tuple_update()/tuple_delete(), which
   returns TM_Updated.
2. Lock tuple with tuple_lock().
3. Re-evaluate plan qual (recheck if we still need to update/delete and
   calculate the new tuple for update).
4. Second attempt to update/delete tuple with tuple_update()/tuple_delete().
   This attempt should be successful, since the tuple was previously locked.

This commit eliminates step 2 by taking the lock during the first
tuple_update()/tuple_delete() call.  The heap table access method saves some
effort by checking the updated tuple once instead of twice.  Future
undo-based table access methods, which will start from the latest row version,
can immediately place a lock there.

Also, this commit makes tuple_update()/tuple_delete() optionally save the old
tuple into the dedicated slot.  That saves efforts on re-fetching tuples in
certain cases.

The code in nodeModifyTable.c is simplified by removing the nested switch/case.

Discussion: https://postgr.es/m/CAPpHfdua-YFw3XTprfutzGp28xXLigFtzNbuFY8yPhqeq6X5kg%40mail.gmail.com
Reviewed-by: Aleksander Alekseev, Pavel Borisov, Vignesh C, Mason Sharp
Reviewed-by: Andres Freund, Chris Travers
 		2024-03-26 01:27:56 +02:00
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amapi.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
amvalidate.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
attmap.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
attnum.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
brin.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
brin_internal.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
brin_page.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
brin_pageops.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
brin_revmap.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
brin_tuple.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
brin_xlog.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
bufmask.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
clog.h Improve performance of subsystems on top of SLRU 2024-02-28 17:05:31 +01:00
commit_ts.h Improve performance of subsystems on top of SLRU 2024-02-28 17:05:31 +01:00
detoast.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
genam.h Add try_index_open(), conditional variant of index_open() 2024-01-18 15:04:24 +09:00
generic_xlog.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
gin.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
gin_private.h Use new overflow-safe integer comparison functions. 2024-02-16 14:05:36 -06:00
ginblock.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
ginxlog.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
gist.h Add temporal PRIMARY KEY and UNIQUE constraints 2024-01-24 16:34:37 +01:00
gist_private.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
gistscan.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
gistxlog.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
hash.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
hash_xlog.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
heapam.h Allow locking updated tuples in tuple_update() and tuple_delete() 2024-03-26 01:27:56 +02:00
heapam_xlog.h Merge prune, freeze and vacuum WAL record formats 2024-03-25 14:59:58 +02:00
heaptoast.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
hio.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
htup.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
htup_details.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
itup.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
multixact.h Improve performance of subsystems on top of SLRU 2024-02-28 17:05:31 +01:00
nbtree.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
nbtxlog.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
parallel.h Remove unused ParallelWorkerInfo.pid field 2024-03-04 12:56:02 +02:00
printsimple.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
printtup.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
relation.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
reloptions.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
relscan.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
rewriteheap.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
rmgr.h Pre-beta mechanical code beautification. 2022-05-12 15:17:30 -04:00
rmgrdesc_utils.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
rmgrlist.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
sdir.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
sequence.h Introduce sequence_*() access functions 2024-02-26 16:04:59 +09:00
session.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
skey.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
slru.h Improve performance of subsystems on top of SLRU 2024-02-28 17:05:31 +01:00
spgist.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
spgist_private.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
spgxlog.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
stratnum.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
subtrans.h Improve performance of subsystems on top of SLRU 2024-02-28 17:05:31 +01:00
syncscan.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
sysattr.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
table.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
tableam.h Allow locking updated tuples in tuple_update() and tuple_delete() 2024-03-26 01:27:56 +02:00
tidstore.h Add TIDStore, to store sets of TIDs (ItemPointerData) efficiently. 2024-03-21 10:08:42 +09:00
timeline.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
toast_compression.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
toast_helper.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
toast_internals.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
transam.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
tsmapi.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
tupconvert.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
tupdesc.h Separate equalRowTypes() from equalTupleDescs() 2024-03-17 05:58:04 +01:00
tupdesc_details.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
tupmacs.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
twophase.h Replace BackendIds with 0-based ProcNumbers 2024-03-03 19:38:22 +02:00
twophase_rmgr.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
valid.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
visibilitymap.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
visibilitymapdefs.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xact.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlog.h Read WAL directly from WAL buffers. 2024-02-12 11:11:22 -08:00
xlog_internal.h Merge prune, freeze and vacuum WAL record formats 2024-03-25 14:59:58 +02:00
xlogarchive.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogbackup.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogdefs.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xloginsert.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogprefetcher.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogreader.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogrecord.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogrecovery.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogstats.h Update copyright for 2024 2024-01-03 20:49:05 -05:00
xlogutils.h Update copyright for 2024 2024-01-03 20:49:05 -05:00