Fix partition table's REPLICA IDENTITY checking on the subscriber.

In logical replication, we will check if the target table on the
subscriber is updatable by comparing the replica identity of the table on
the publisher with the table on the subscriber. When the target table is a
partitioned table, we only check its replica identity but not for the
partition tables. This leads to assertion failure while applying changes
for update/delete as we expect those to succeed only when the
corresponding partition table has a primary key or has a replica
identity defined.

Fix it by checking the replica identity of the partition table while
applying changes.

Reported-by: Shi Yu
Author: Shi Yu, Hou Zhijie
Reviewed-by: Amit Langote, Amit Kapila
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/OSZPR01MB6310F46CD425A967E4AEF736FDA49@OSZPR01MB6310.jpnprd01.prod.outlook.com

diff --git a/src/backend/replication/logical/relation.c b/src/backend/replication/logical/relation.c
index 026d2c2af47682a2b023d6ad9772c567a2592732..b764ca97e3b1fcdc68606f3d71d1f253cec68543 100644 (file)
--- a/src/backend/replication/logical/relation.c
+++ b/src/backend/replication/logical/relation.c
@@ -213,6 +213,67 @@ logicalrep_rel_att_by_name(LogicalRepRelation *remoterel, const char *attname)
        return -1;
 }
 
+/*
+ * Check if replica identity matches and mark the updatable flag.
+ *
+ * We allow for stricter replica identity (fewer columns) on subscriber as
+ * that will not stop us from finding unique tuple. IE, if publisher has
+ * identity (id,timestamp) and subscriber just (id) this will not be a
+ * problem, but in the opposite scenario it will.
+ *
+ * We just mark the relation entry as not updatable here if the local
+ * replica identity is found to be insufficient for applying
+ * updates/deletes (inserts don't care!) and leave it to
+ * check_relation_updatable() to throw the actual error if needed.
+ */
+static void
+logicalrep_rel_mark_updatable(LogicalRepRelMapEntry *entry)
+{
+       Bitmapset  *idkey;
+       LogicalRepRelation *remoterel = &entry->remoterel;
+       int                     i;
+
+       entry->updatable = true;
+
+       idkey = RelationGetIndexAttrBitmap(entry->localrel,
+                                                                          INDEX_ATTR_BITMAP_IDENTITY_KEY);
+       /* fallback to PK if no replica identity */
+       if (idkey == NULL)
+       {
+               idkey = RelationGetIndexAttrBitmap(entry->localrel,
+                                                                                  INDEX_ATTR_BITMAP_PRIMARY_KEY);
+
+               /*
+                * If no replica identity index and no PK, the published table must
+                * have replica identity FULL.
+                */
+               if (idkey == NULL && remoterel->replident != REPLICA_IDENTITY_FULL)
+                       entry->updatable = false;
+       }
+
+       i = -1;
+       while ((i = bms_next_member(idkey, i)) >= 0)
+       {
+               int                     attnum = i + FirstLowInvalidHeapAttributeNumber;
+
+               if (!AttrNumberIsForUserDefinedAttr(attnum))
+                       ereport(ERROR,
+                                       (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+                                        errmsg("logical replication target relation \"%s.%s\" uses "
+                                                       "system columns in REPLICA IDENTITY index",
+                                                       remoterel->nspname, remoterel->relname)));
+
+               attnum = AttrNumberGetAttrOffset(attnum);
+
+               if (entry->attrmap->attnums[attnum] < 0 ||
+                       !bms_is_member(entry->attrmap->attnums[attnum], remoterel->attkeys))
+               {
+                       entry->updatable = false;
+                       break;
+               }
+       }
+}
+
 /*
  * Open the local relation associated with the remote one.
  *
@@ -272,7 +333,6 @@ logicalrep_rel_open(LogicalRepRelId remoteid, LOCKMODE lockmode)
        {
                Oid                     relid;
                int                     found;
-               Bitmapset  *idkey;
                TupleDesc       desc;
                MemoryContext oldctx;
                int                     i;
@@ -332,54 +392,10 @@ logicalrep_rel_open(LogicalRepRelId remoteid, LOCKMODE lockmode)
                                                        remoterel->nspname, remoterel->relname)));
 
                /*
-                * Check that replica identity matches. We allow for stricter replica
-                * identity (fewer columns) on subscriber as that will not stop us
-                * from finding unique tuple. IE, if publisher has identity
-                * (id,timestamp) and subscriber just (id) this will not be a problem,
-                * but in the opposite scenario it will.
-                *
-                * Don't throw any error here just mark the relation entry as not
-                * updatable, as replica identity is only for updates and deletes but
-                * inserts can be replicated even without it.
+                * Set if the table's replica identity is enough to apply
+                * update/delete.
                 */
-               entry->updatable = true;
-               idkey = RelationGetIndexAttrBitmap(entry->localrel,
-                                                                                  INDEX_ATTR_BITMAP_IDENTITY_KEY);
-               /* fallback to PK if no replica identity */
-               if (idkey == NULL)
-               {
-                       idkey = RelationGetIndexAttrBitmap(entry->localrel,
-                                                                                          INDEX_ATTR_BITMAP_PRIMARY_KEY);
-
-                       /*
-                        * If no replica identity index and no PK, the published table
-                        * must have replica identity FULL.
-                        */
-                       if (idkey == NULL && remoterel->replident != REPLICA_IDENTITY_FULL)
-                               entry->updatable = false;
-               }
-
-               i = -1;
-               while ((i = bms_next_member(idkey, i)) >= 0)
-               {
-                       int                     attnum = i + FirstLowInvalidHeapAttributeNumber;
-
-                       if (!AttrNumberIsForUserDefinedAttr(attnum))
-                               ereport(ERROR,
-                                               (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-                                                errmsg("logical replication target relation \"%s.%s\" uses "
-                                                               "system columns in REPLICA IDENTITY index",
-                                                               remoterel->nspname, remoterel->relname)));
-
-                       attnum = AttrNumberGetAttrOffset(attnum);
-
-                       if (entry->attrmap->attnums[attnum] < 0 ||
-                               !bms_is_member(entry->attrmap->attnums[attnum], remoterel->attkeys))
-                       {
-                               entry->updatable = false;
-                               break;
-                       }
-               }
+               logicalrep_rel_mark_updatable(entry);
 
                entry->localrelvalid = true;
        }
@@ -619,7 +635,8 @@ logicalrep_partition_open(LogicalRepRelMapEntry *root,
                           attrmap->maplen * sizeof(AttrNumber));
        }
 
-       entry->updatable = root->updatable;
+       /* Set if the table's replica identity is enough to apply update/delete. */
+       logicalrep_rel_mark_updatable(entry);
 
        entry->localrelvalid = true;
 

diff --git a/src/backend/replication/logical/worker.c b/src/backend/replication/logical/worker.c
index 8eafd61cdbd9234303aa1f62a71b415ba0a0e22e..4c4165da1eb6413e5b723acca5cf5b2700a5d76d 100644 (file)
--- a/src/backend/replication/logical/worker.c
+++ b/src/backend/replication/logical/worker.c
@@ -730,6 +730,13 @@ apply_handle_insert_internal(ResultRelInfo *relinfo,
 static void
 check_relation_updatable(LogicalRepRelMapEntry *rel)
 {
+       /*
+        * For partitioned tables, we only need to care if the target partition is
+        * updatable (aka has PK or RI defined for it).
+        */
+       if (rel->localrel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
+               return;
+
        /* Updatable, no error. */
        if (rel->updatable)
                return;
@@ -1064,6 +1071,8 @@ apply_handle_tuple_routing(ApplyExecutionData *edata,
        PartitionRoutingInfo *partinfo;
        TupleConversionMap *map;
        MemoryContext oldctx;
+       LogicalRepRelMapEntry *part_entry = NULL;
+       AttrMap    *attrmap = NULL;
 
        /* ModifyTableState is needed for ExecFindPartition(). */
        edata->mtstate = mtstate = makeNode(ModifyTableState);
@@ -1097,8 +1106,11 @@ apply_handle_tuple_routing(ApplyExecutionData *edata,
                remoteslot_part = table_slot_create(partrel, &estate->es_tupleTable);
        map = partinfo->pi_RootToPartitionMap;
        if (map != NULL)
-               remoteslot_part = execute_attr_map_slot(map->attrMap, remoteslot,
+       {
+               attrmap = map->attrMap;
+               remoteslot_part = execute_attr_map_slot(attrmap, remoteslot,
                                                                                                remoteslot_part);
+       }
        else
        {
                remoteslot_part = ExecCopySlot(remoteslot_part, remoteslot);
@@ -1106,6 +1118,14 @@ apply_handle_tuple_routing(ApplyExecutionData *edata,
        }
        MemoryContextSwitchTo(oldctx);
 
+       /* Check if we can do the update or delete on the leaf partition. */
+       if (operation == CMD_UPDATE || operation == CMD_DELETE)
+       {
+               part_entry = logicalrep_partition_open(relmapentry, partrel,
+                                                                                          attrmap);
+               check_relation_updatable(part_entry);
+       }
+
        estate->es_result_relation_info = partrelinfo;
        switch (operation)
        {
@@ -1129,15 +1149,10 @@ apply_handle_tuple_routing(ApplyExecutionData *edata,
                         * suitable partition.
                         */
                        {
-                               AttrMap    *attrmap = map ? map->attrMap : NULL;
-                               LogicalRepRelMapEntry *part_entry;
                                TupleTableSlot *localslot;
                                ResultRelInfo *partrelinfo_new;
                                bool            found;
 
-                               part_entry = logicalrep_partition_open(relmapentry, partrel,
-                                                                                                          attrmap);
-
                                /* Get the matching local tuple from the partition. */
                                found = FindReplTupleInLocalRel(estate, partrel,
                                                                                                &part_entry->remoterel,

diff --git a/src/test/subscription/t/013_partition.pl b/src/test/subscription/t/013_partition.pl
index 8a1ec55f24feb725c9c6128f8dd9e6dd816dc6b5..4debbfe55f38c82fe391eef6d59879dd66852762 100644 (file)
--- a/src/test/subscription/t/013_partition.pl
+++ b/src/test/subscription/t/013_partition.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 70;
+use Test::More tests => 71;
 
 # setup
 
@@ -853,3 +853,17 @@ $node_publisher->wait_for_catchup('sub2');
 $result = $node_subscriber2->safe_psql('postgres',
        "SELECT a, b, c FROM tab5 ORDER BY 1");
 is($result, qq(3||1), 'updates of tab5 replicated correctly after altering table on publisher');
+
+# Test that replication works correctly as long as the leaf partition
+# has the necessary REPLICA IDENTITY, even though the actual target
+# partitioned table does not.
+$node_subscriber2->safe_psql('postgres',
+       "ALTER TABLE tab5 REPLICA IDENTITY NOTHING");
+
+$node_publisher->safe_psql('postgres', "UPDATE tab5 SET a = 4 WHERE a = 3");
+
+$node_publisher->wait_for_catchup('sub2');
+
+$result = $node_subscriber2->safe_psql('postgres',
+       "SELECT a, b, c FROM tab5_1 ORDER BY 1");
+is($result, qq(4||1), 'updates of tab5 replicated correctly');