From: Álvaro Herrera Date: Mon, 11 May 2026 16:17:46 +0000 (+0200) Subject: Fix REPACK with WITHOUT OVERLAPS replica identity indexes X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=36f52a59b31502213a01fb4b0a89afc0f3bfd21d;p=thirdparty%2Fpostgresql.git Fix REPACK with WITHOUT OVERLAPS replica identity indexes REPACK replay builds scan keys for the replica identity index, but it hard-coded BTEqualStrategyNumber when looking up the equality operator. That is not correct for non-btree identity indexes, such as the GiST indexes created for WITHOUT OVERLAPS primary keys. In addition, find_target_tuple() accepted the first tuple returned by the identity index scan, which is unsafe for lossy index scans because the index AM may return false positives with xs_recheck set. Fix this by using IndexAmTranslateCompareType() to translate COMPARE_EQ to the equality strategy number for the index AM, and by continuing the scan when recheck is required until a candidate tuple matches the locator tuple on all replica identity key columns. The recheck uses the same equality operator functions as the identity index scan keys, preserving ScanKey argument ordering. Author: Chao Li Reviewed-by: Kirill Reshke Reviewed-by: Álvaro Herrera Discussion: https://postgr.es/m/7B0EC0EC-5461-41EF-9B31-F9BBE608DEA5@gmail.com --- diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index 9a199dd9bfb..860e2aecbe9 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -118,6 +118,9 @@ typedef struct ChangeContext ScanKey cc_ident_key; int cc_ident_key_nentries; + /* The latest column we need to deform to have the tuple identity */ + AttrNumber cc_last_key_attno; + /* Sequential number of the file containing the changes. */ int cc_file_seq; } ChangeContext; @@ -182,6 +185,9 @@ static void adjust_toast_pointers(Relation relation, TupleTableSlot *dest, static bool find_target_tuple(Relation rel, ChangeContext *chgcxt, TupleTableSlot *locator, TupleTableSlot *retrieved); +static bool identity_key_equal(ChangeContext *chgcxt, + TupleTableSlot *locator, + TupleTableSlot *candidate); static void process_concurrent_changes(XLogRecPtr end_of_wal, ChangeContext *chgcxt, bool done); @@ -2807,7 +2813,7 @@ find_target_tuple(Relation rel, ChangeContext *chgcxt, TupleTableSlot *locator, { Form_pg_index idx = chgcxt->cc_ident_index->rd_index; IndexScanDesc scan; - bool retval; + bool retval = false; /* * Scan key is passed by caller, so it does not have to be constructed @@ -2829,12 +2835,61 @@ find_target_tuple(Relation rel, ChangeContext *chgcxt, TupleTableSlot *locator, scan = index_beginscan(rel, chgcxt->cc_ident_index, GetActiveSnapshot(), NULL, chgcxt->cc_ident_key_nentries, 0, 0); index_rescan(scan, chgcxt->cc_ident_key, chgcxt->cc_ident_key_nentries, NULL, 0); - retval = index_getnext_slot(scan, ForwardScanDirection, retrieved); + while (index_getnext_slot(scan, ForwardScanDirection, retrieved)) + { + /* Be wary of temporal constraints */ + if (scan->xs_recheck && !identity_key_equal(chgcxt, locator, retrieved)) + { + CHECK_FOR_INTERRUPTS(); + continue; + } + + retval = true; + break; + } index_endscan(scan); return retval; } +/* + * Check whether the candidate tuple matches the locator tuple on all replica + * identity key columns, using the same equality operators as the identity + * index scan. The locator tuple has already been loaded into cc_ident_key. + * + * This is needed to filter lossy index matches, such as GiST multirange scans + * used for temporal constraints. + */ +static bool +identity_key_equal(ChangeContext *chgcxt, TupleTableSlot *locator, + TupleTableSlot *candidate) +{ + slot_getsomeattrs(locator, chgcxt->cc_last_key_attno); + slot_getsomeattrs(candidate, chgcxt->cc_last_key_attno); + + for (int i = 0; i < chgcxt->cc_ident_key_nentries; i++) + { + ScanKey entry = &chgcxt->cc_ident_key[i]; + AttrNumber attno = chgcxt->cc_ident_index->rd_index->indkey.values[i]; + + Assert(attno > 0); + + if (locator->tts_isnull[attno - 1] != candidate->tts_isnull[attno - 1]) + return false; + + if (locator->tts_isnull[attno - 1]) + continue; + + if (!DatumGetBool(FunctionCall2Coll(&entry->sk_func, + entry->sk_collation, + candidate->tts_values[attno - 1], + entry->sk_argument))) + return false; + } + + return true; +} + /* * Decode and apply concurrent changes, up to (and including) the record whose * LSN is 'end_of_wal'. @@ -2944,28 +2999,46 @@ initialize_change_context(ChangeContext *chgcxt, opcintype, opno, opcode; + StrategyNumber eq_strategy; entry = &chgcxt->cc_ident_key[i]; opfamily = chgcxt->cc_ident_index->rd_opfamily[i]; opcintype = chgcxt->cc_ident_index->rd_opcintype[i]; + eq_strategy = IndexAmTranslateCompareType(COMPARE_EQ, + chgcxt->cc_ident_index->rd_rel->relam, + opfamily, false); + if (eq_strategy == InvalidStrategy) + elog(ERROR, "could not find equality strategy for index operator family %u for type %u", + opfamily, opcintype); opno = get_opfamily_member(opfamily, opcintype, opcintype, - BTEqualStrategyNumber); + eq_strategy); if (!OidIsValid(opno)) - elog(ERROR, "failed to find = operator for type %u", opcintype); + elog(ERROR, "missing operator %d(%u,%u) in opfamily %u", + eq_strategy, opcintype, opcintype, opfamily); opcode = get_opcode(opno); if (!OidIsValid(opcode)) - elog(ERROR, "failed to find = operator for operator %u", opno); + elog(ERROR, "missing oprcode for operator %u", opno); /* Initialize everything but argument. */ ScanKeyInit(entry, i + 1, - BTEqualStrategyNumber, opcode, + eq_strategy, opcode, (Datum) 0); entry->sk_collation = chgcxt->cc_ident_index->rd_indcollation[i]; } } + /* Determine the last column we must deform to read the identity */ + chgcxt->cc_last_key_attno = InvalidAttrNumber; + for (int i = 0; i < chgcxt->cc_ident_key_nentries; i++) + { + AttrNumber attno = chgcxt->cc_ident_index->rd_index->indkey.values[i]; + + Assert(attno > 0); + chgcxt->cc_last_key_attno = Max(chgcxt->cc_last_key_attno, attno); + } + chgcxt->cc_file_seq = WORKER_FILE_SNAPSHOT + 1; } diff --git a/src/test/modules/injection_points/Makefile b/src/test/modules/injection_points/Makefile index f057d143d1a..c01d2fb095c 100644 --- a/src/test/modules/injection_points/Makefile +++ b/src/test/modules/injection_points/Makefile @@ -15,6 +15,8 @@ REGRESS_OPTS = --dlpath=$(top_builddir)/src/test/regress ISOLATION = basic \ inplace \ repack \ + repack_temporal \ + repack_temporal_multirange \ repack_toast \ syscache-update-pruned \ heap_lock_update diff --git a/src/test/modules/injection_points/expected/repack_temporal.out b/src/test/modules/injection_points/expected/repack_temporal.out new file mode 100644 index 00000000000..ea02089c79a --- /dev/null +++ b/src/test/modules/injection_points/expected/repack_temporal.out @@ -0,0 +1,68 @@ +Parsed test spec with 2 sessions + +starting permutation: wait_before_lock update_target check_after_update wakeup_before_lock check_after_repack +injection_points_attach +----------------------- + +(1 row) + +step wait_before_lock: + REPACK (CONCURRENTLY) repack_temporal USING INDEX rt_pkey; + +step update_target: + UPDATE repack_temporal + SET label = 'updated' + WHERE id = '[2,3)' AND valid_at = '[2000-01-10,2000-01-20)'; + +step check_after_update: + INSERT INTO relfilenodes(node) + SELECT relfilenode FROM pg_class WHERE relname = 'repack_temporal'; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal + ORDER BY id, valid_at, label; + +id |valid_at |label +------+-----------------------+------- +[1,10)|[01-01-2000,02-01-2000)|other +[2,3) |[01-10-2000,01-20-2000)|updated +(2 rows) + +step wakeup_before_lock: + SELECT injection_points_wakeup('repack-concurrently-before-lock'); + +injection_points_wakeup +----------------------- + +(1 row) + +step wait_before_lock: <... completed> +step check_after_repack: + INSERT INTO relfilenodes(node) + SELECT relfilenode FROM pg_class WHERE relname = 'repack_temporal'; + + -- Expect 2, proving that repack has rewritten the table + SELECT count(DISTINCT node) FROM relfilenodes; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal + ORDER BY id, valid_at, label; + +count +----- + 2 +(1 row) + +id |valid_at |label +------+-----------------------+------- +[1,10)|[01-01-2000,02-01-2000)|other +[2,3) |[01-10-2000,01-20-2000)|updated +(2 rows) + +injection_points_detach +----------------------- + +(1 row) + diff --git a/src/test/modules/injection_points/expected/repack_temporal_multirange.out b/src/test/modules/injection_points/expected/repack_temporal_multirange.out new file mode 100644 index 00000000000..a2e015c3b85 --- /dev/null +++ b/src/test/modules/injection_points/expected/repack_temporal_multirange.out @@ -0,0 +1,74 @@ +Parsed test spec with 2 sessions + +starting permutation: wait_before_lock update_target check_after_update wakeup_before_lock final_check +injection_points_attach +----------------------- + +(1 row) + +step wait_before_lock: + REPACK (CONCURRENTLY) repack_temporal_multirange + USING INDEX rtm_pkey; + +step update_target: + UPDATE repack_temporal_multirange + SET label = 'updated' + WHERE id = int4multirange(int4range(1, 7)) + AND valid_at = datemultirange(daterange('2000-01-01', '2000-02-01')); + +step check_after_update: + INSERT INTO relfilenodes(node) + SELECT relfilenode + FROM pg_class + WHERE relname = 'repack_temporal_multirange'; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal_multirange + ORDER BY id, valid_at, label; + +id |valid_at |label +-------------+-------------------------+------- +{[1,3),[5,7)}|{[01-01-2000,02-01-2000)}|other +{[1,7)} |{[01-01-2000,02-01-2000)}|updated +(2 rows) + +step wakeup_before_lock: + SELECT injection_points_wakeup('repack-concurrently-before-lock'); + +injection_points_wakeup +----------------------- + +(1 row) + +step wait_before_lock: <... completed> +step final_check: + INSERT INTO relfilenodes(node) + SELECT relfilenode + FROM pg_class + WHERE relname = 'repack_temporal_multirange'; + + -- Expect 2, proving that repack has rewritten the table + SELECT count(DISTINCT node) FROM relfilenodes; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal_multirange + ORDER BY id, valid_at, label; + +count +----- + 2 +(1 row) + +id |valid_at |label +-------------+-------------------------+------- +{[1,3),[5,7)}|{[01-01-2000,02-01-2000)}|other +{[1,7)} |{[01-01-2000,02-01-2000)}|updated +(2 rows) + +injection_points_detach +----------------------- + +(1 row) + diff --git a/src/test/modules/injection_points/meson.build b/src/test/modules/injection_points/meson.build index fb1418e2caa..59dba1cb023 100644 --- a/src/test/modules/injection_points/meson.build +++ b/src/test/modules/injection_points/meson.build @@ -46,6 +46,8 @@ tests += { 'basic', 'inplace', 'repack', + 'repack_temporal', + 'repack_temporal_multirange', 'repack_toast', 'syscache-update-pruned', 'heap_lock_update', diff --git a/src/test/modules/injection_points/specs/repack_temporal.spec b/src/test/modules/injection_points/specs/repack_temporal.spec new file mode 100644 index 00000000000..c9fd3f61a84 --- /dev/null +++ b/src/test/modules/injection_points/specs/repack_temporal.spec @@ -0,0 +1,90 @@ +# REPACK (CONCURRENTLY) on a temporal replica identity index. +# +# The table's replica identity is a GiST index created by a temporal primary +# key. A concurrent UPDATE changes a non-key column of one row, while another +# row overlaps it on all indexed columns. Replay must still find the exact +# target row. +setup +{ + CREATE EXTENSION injection_points; + + CREATE TABLE repack_temporal ( + id int4range, + valid_at daterange, + label text, + CONSTRAINT rt_pkey PRIMARY KEY (id, valid_at WITHOUT OVERLAPS) + ); + + ALTER TABLE repack_temporal REPLICA IDENTITY USING INDEX rt_pkey; + + INSERT INTO repack_temporal(id, valid_at, label) + VALUES + ('[1,10)', '[2000-01-01,2000-02-01)', 'other'), + ('[2,3)', '[2000-01-10,2000-01-20)', 'target'); + + CREATE TABLE relfilenodes(node oid); +} + +teardown +{ + DROP TABLE repack_temporal; + DROP EXTENSION injection_points; + DROP TABLE relfilenodes; +} + +session s1 +setup +{ + SELECT injection_points_set_local(); + SELECT injection_points_attach('repack-concurrently-before-lock', 'wait'); +} +step wait_before_lock +{ + REPACK (CONCURRENTLY) repack_temporal USING INDEX rt_pkey; +} +step check_after_repack +{ + INSERT INTO relfilenodes(node) + SELECT relfilenode FROM pg_class WHERE relname = 'repack_temporal'; + + -- Expect 2, proving that repack has rewritten the table + SELECT count(DISTINCT node) FROM relfilenodes; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal + ORDER BY id, valid_at, label; +} +teardown +{ + SELECT injection_points_detach('repack-concurrently-before-lock'); +} + +session s2 +step update_target +{ + UPDATE repack_temporal + SET label = 'updated' + WHERE id = '[2,3)' AND valid_at = '[2000-01-10,2000-01-20)'; +} +step check_after_update +{ + INSERT INTO relfilenodes(node) + SELECT relfilenode FROM pg_class WHERE relname = 'repack_temporal'; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal + ORDER BY id, valid_at, label; +} +step wakeup_before_lock +{ + SELECT injection_points_wakeup('repack-concurrently-before-lock'); +} + +permutation + wait_before_lock + update_target + check_after_update + wakeup_before_lock + check_after_repack diff --git a/src/test/modules/injection_points/specs/repack_temporal_multirange.spec b/src/test/modules/injection_points/specs/repack_temporal_multirange.spec new file mode 100644 index 00000000000..8150c0b4ba8 --- /dev/null +++ b/src/test/modules/injection_points/specs/repack_temporal_multirange.spec @@ -0,0 +1,102 @@ +# REPACK (CONCURRENTLY) on a temporal replica identity index with lossy +# multirange equality. +# +# The leading identity column is of type int4multirange. Two distinct rows +# have different multirange values but the same union range, so GiST equality +# can produce both as candidates and requires exact recheck. +setup +{ + CREATE EXTENSION injection_points; + + CREATE TABLE repack_temporal_multirange ( + id int4multirange, + valid_at datemultirange, + label text, + CONSTRAINT rtm_pkey PRIMARY KEY (id, valid_at WITHOUT OVERLAPS) + ); + + ALTER TABLE repack_temporal_multirange + REPLICA IDENTITY USING INDEX rtm_pkey; + + -- (1,3)+(5,7) is the same union range of (1-7), but needs recheck + INSERT INTO repack_temporal_multirange(id, valid_at, label) + VALUES + (int4multirange(int4range(1, 3), int4range(5, 7)), + datemultirange(daterange('2000-01-01', '2000-02-01')), + 'other'), + (int4multirange(int4range(1, 7)), + datemultirange(daterange('2000-01-01', '2000-02-01')), + 'target'); + + CREATE TABLE relfilenodes(node oid); +} + +teardown +{ + DROP TABLE repack_temporal_multirange; + DROP EXTENSION injection_points; + DROP TABLE relfilenodes; +} + +session s1 +setup +{ + SELECT injection_points_set_local(); + SELECT injection_points_attach('repack-concurrently-before-lock', 'wait'); +} +step wait_before_lock +{ + REPACK (CONCURRENTLY) repack_temporal_multirange + USING INDEX rtm_pkey; +} +step final_check +{ + INSERT INTO relfilenodes(node) + SELECT relfilenode + FROM pg_class + WHERE relname = 'repack_temporal_multirange'; + + -- Expect 2, proving that repack has rewritten the table + SELECT count(DISTINCT node) FROM relfilenodes; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal_multirange + ORDER BY id, valid_at, label; +} +teardown +{ + SELECT injection_points_detach('repack-concurrently-before-lock'); +} + +session s2 +step update_target +{ + UPDATE repack_temporal_multirange + SET label = 'updated' + WHERE id = int4multirange(int4range(1, 7)) + AND valid_at = datemultirange(daterange('2000-01-01', '2000-02-01')); +} +step check_after_update +{ + INSERT INTO relfilenodes(node) + SELECT relfilenode + FROM pg_class + WHERE relname = 'repack_temporal_multirange'; + + -- Expect 2 rows + SELECT id, valid_at, label + FROM repack_temporal_multirange + ORDER BY id, valid_at, label; +} +step wakeup_before_lock +{ + SELECT injection_points_wakeup('repack-concurrently-before-lock'); +} + +permutation + wait_before_lock + update_target + check_after_update + wakeup_before_lock + final_check