1 files changed, 40 insertions, 16 deletions

diff --git a/src/backend/replication/logical/tablesync.c b/src/backend/replication/logical/tablesync.c
index d4b5d210e3e..118503fcb76 100644
--- a/src/backend/replication/logical/tablesync.c
+++ b/src/backend/replication/logical/tablesync.c
@@ -787,23 +787,27 @@ copy_read_data(void *outbuf, int minread, int maxread)
 
 /*
  * Get information about remote relation in similar fashion the RELATION
- * message provides during replication. This function also returns the relation
- * qualifications to be used in the COPY command.
+ * message provides during replication.
+ *
+ * This function also returns (a) the relation qualifications to be used in
+ * the COPY command, and (b) whether the remote relation has published any
+ * generated column.
  */
 static void
-fetch_remote_table_info(char *nspname, char *relname,
-						LogicalRepRelation *lrel, List **qual)
+fetch_remote_table_info(char *nspname, char *relname, LogicalRepRelation *lrel,
+						List **qual, bool *gencol_published)
 {
 	WalRcvExecResult *res;
 	StringInfoData cmd;
 	TupleTableSlot *slot;
 	Oid			tableRow[] = {OIDOID, CHAROID, CHAROID};
-	Oid			attrRow[] = {INT2OID, TEXTOID, OIDOID, BOOLOID};
+	Oid			attrRow[] = {INT2OID, TEXTOID, OIDOID, BOOLOID, BOOLOID};
 	Oid			qualRow[] = {TEXTOID};
 	bool		isnull;
 	int			natt;
 	StringInfo	pub_names = NULL;
 	Bitmapset  *included_cols = NULL;
+	int			server_version = walrcv_server_version(LogRepWorkerWalRcvConn);
 
 	lrel->nspname = nspname;
 	lrel->relname = relname;
@@ -851,7 +855,7 @@ fetch_remote_table_info(char *nspname, char *relname,
 	 * We need to do this before fetching info about column names and types,
 	 * so that we can skip columns that should not be replicated.
 	 */
-	if (walrcv_server_version(LogRepWorkerWalRcvConn) >= 150000)
+	if (server_version >= 150000)
 	{
 		WalRcvExecResult *pubres;
 		TupleTableSlot *tslot;
@@ -941,7 +945,13 @@ fetch_remote_table_info(char *nspname, char *relname,
 					 "SELECT a.attnum,"
 					 "       a.attname,"
 					 "       a.atttypid,"
-					 "       a.attnum = ANY(i.indkey)"
+					 "       a.attnum = ANY(i.indkey)");
+
+	/* Generated columns can be replicated since version 18. */
+	if (server_version >= 180000)
+		appendStringInfo(&cmd, ", a.attgenerated != ''");
+
+	appendStringInfo(&cmd,
 					 "  FROM pg_catalog.pg_attribute a"
 					 "  LEFT JOIN pg_catalog.pg_index i"
 					 "       ON (i.indexrelid = pg_get_replica_identity_index(%u))"
@@ -950,11 +960,11 @@ fetch_remote_table_info(char *nspname, char *relname,
 					 "   AND a.attrelid = %u"
 					 " ORDER BY a.attnum",
 					 lrel->remoteid,
-					 (walrcv_server_version(LogRepWorkerWalRcvConn) >= 120000 ?
+					 (server_version >= 120000 && server_version < 180000 ?
 					  "AND a.attgenerated = ''" : ""),
 					 lrel->remoteid);
 	res = walrcv_exec(LogRepWorkerWalRcvConn, cmd.data,
-					  lengthof(attrRow), attrRow);
+					  server_version >= 180000 ? lengthof(attrRow) : lengthof(attrRow) - 1, attrRow);
 
 	if (res->status != WALRCV_OK_TUPLES)
 		ereport(ERROR,
@@ -998,6 +1008,13 @@ fetch_remote_table_info(char *nspname, char *relname,
 		if (DatumGetBool(slot_getattr(slot, 4, &isnull)))
 			lrel->attkeys = bms_add_member(lrel->attkeys, natt);
 
+		/* Remember if the remote table has published any generated column. */
+		if (server_version >= 180000 && !(*gencol_published))
+		{
+			*gencol_published = DatumGetBool(slot_getattr(slot, 5, &isnull));
+			Assert(!isnull);
+		}
+
 		/* Should never happen. */
 		if (++natt >= MaxTupleAttributeNumber)
 			elog(ERROR, "too many columns in remote table \"%s.%s\"",
@@ -1030,7 +1047,7 @@ fetch_remote_table_info(char *nspname, char *relname,
 	 * 3) one of the subscribed publications is declared as TABLES IN SCHEMA
 	 * that includes this relation
 	 */
-	if (walrcv_server_version(LogRepWorkerWalRcvConn) >= 150000)
+	if (server_version >= 150000)
 	{
 		/* Reuse the already-built pub_names. */
 		Assert(pub_names != NULL);
@@ -1106,10 +1123,12 @@ copy_table(Relation rel)
 	List	   *attnamelist;
 	ParseState *pstate;
 	List	   *options = NIL;
+	bool		gencol_published = false;
 
 	/* Get the publisher relation info. */
 	fetch_remote_table_info(get_namespace_name(RelationGetNamespace(rel)),
-							RelationGetRelationName(rel), &lrel, &qual);
+							RelationGetRelationName(rel), &lrel, &qual,
+							&gencol_published);
 
 	/* Put the relation into relmap. */
 	logicalrep_relmap_update(&lrel);
@@ -1121,8 +1140,8 @@ copy_table(Relation rel)
 	/* Start copy on the publisher. */
 	initStringInfo(&cmd);
 
-	/* Regular table with no row filter */
-	if (lrel.relkind == RELKIND_RELATION && qual == NIL)
+	/* Regular table with no row filter or generated columns */
+	if (lrel.relkind == RELKIND_RELATION && qual == NIL && !gencol_published)
 	{
 		appendStringInfo(&cmd, "COPY %s",
 						 quote_qualified_identifier(lrel.nspname, lrel.relname));
@@ -1153,9 +1172,14 @@ copy_table(Relation rel)
 	{
 		/*
 		 * For non-tables and tables with row filters, we need to do COPY
-		 * (SELECT ...), but we can't just do SELECT * because we need to not
-		 * copy generated columns. For tables with any row filters, build a
-		 * SELECT query with OR'ed row filters for COPY.
+		 * (SELECT ...), but we can't just do SELECT * because we may need to
+		 * copy only subset of columns including generated columns. For tables
+		 * with any row filters, build a SELECT query with OR'ed row filters
+		 * for COPY.
+		 *
+		 * We also need to use this same COPY (SELECT ...) syntax when
+		 * generated columns are published, because copy of generated columns
+		 * is not supported by the normal COPY.
 		 */
 		appendStringInfoString(&cmd, "COPY (SELECT ");
 		for (int i = 0; i < lrel.natts; i++)