pg_dump: minor performance improvements from eliminating sub-SELECTs.

Get rid of the "username_subquery" mechanism in favor of doing
local lookups of role names from role OIDs.  The PG backend isn't
terribly smart about scalar SubLinks in SELECT output lists,
so this offers a small performance improvement, at least in
installations with more than a couple of users.  In any case
the old method didn't make for particularly readable SQL code.

While at it, I removed the various custom warning messages about
failing to find an object's owner, in favor of just fatal'ing
in the local lookup function.  AFAIK there is no reason any
longer to treat that as anything but a catalog-corruption case,
and certainly no reason to make translators deal with a dozen
different messages where one would do.  (If it turns out that
fatal() is indeed a bad idea, we can back off to issuing
pg_log_warning() and returning an empty string, resulting in
the same behavior as before, except more consistent.)

Also drop an entirely unnecessary sub-SELECT to check on the
pg_depend status of a sequence relation: we already have a
LEFT JOIN to fetch the row of interest in the FROM clause.

Discussion: https://postgr.es/m/2460369.1640903318@sss.pgh.pa.us

2 files changed, 217 insertions, 214 deletions

diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 7a5851e4c5..ba19746ec3 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -68,6 +68,12 @@
 
 typedef struct
 {
+	Oid			roleoid;		/* role's OID */
+	const char *rolename;		/* role's name */
+} RoleNameItem;
+
+typedef struct
+{
 	const char *descr;			/* comment for an object */
 	Oid			classoid;		/* object class (catalog OID) */
 	Oid			objoid;			/* object OID */
@@ -93,9 +99,6 @@ typedef enum OidOptions
 /* global decls */
 static bool dosync = true;		/* Issue fsync() to make dump durable on disk. */
 
-/* subquery used to convert user ID (eg, datdba) to user name */
-static const char *username_subquery;
-
 static Oid	g_last_builtin_oid; /* value of the last builtin oid */
 
 /* The specified names/patterns should to match at least one entity */
@@ -130,6 +133,10 @@ static const CatalogId nilCatalogId = {0, 0};
 static bool have_extra_float_digits = false;
 static int	extra_float_digits;
 
+/* sorted table of role names */
+static RoleNameItem *rolenames = NULL;
+static int	nrolenames = 0;
+
 /* sorted table of comments */
 static CommentItem *comments = NULL;
 static int	ncomments = 0;
@@ -174,6 +181,8 @@ static void expand_table_name_patterns(Archive *fout,
 static NamespaceInfo *findNamespace(Oid nsoid);
 static void dumpTableData(Archive *fout, const TableDataInfo *tdinfo);
 static void refreshMatViewData(Archive *fout, const TableDataInfo *tdinfo);
+static const char *getRoleName(const char *roleoid_str);
+static void collectRoleNames(Archive *fout);
 static void getAdditionalACLs(Archive *fout);
 static void dumpCommentExtended(Archive *fout, const char *type,
 								const char *name, const char *namespace,
@@ -744,9 +753,6 @@ main(int argc, char **argv)
 	if (fout->isStandby)
 		dopt.no_unlogged_table_data = true;
 
-	/* Select the appropriate subquery to convert user IDs to names */
-	username_subquery = "SELECT rolname FROM pg_catalog.pg_roles WHERE oid =";
-
 	/*
 	 * Find the last built-in OID, if needed (prior to 8.1)
 	 *
@@ -815,6 +821,11 @@ main(int argc, char **argv)
 		dopt.outputBlobs = true;
 
 	/*
+	 * Collect role names so we can map object owner OIDs to names.
+	 */
+	collectRoleNames(fout);
+
+	/*
 	 * Now scan the database and create DumpableObject structs for all the
 	 * objects we intend to dump.
 	 */
@@ -2737,7 +2748,7 @@ dumpDatabase(Archive *fout)
 	int			i_tableoid,
 				i_oid,
 				i_datname,
-				i_dba,
+				i_datdba,
 				i_encoding,
 				i_collate,
 				i_ctype,
@@ -2771,7 +2782,7 @@ dumpDatabase(Archive *fout)
 	if (fout->remoteVersion >= 90300)
 	{
 		appendPQExpBuffer(dbQry, "SELECT tableoid, oid, datname, "
-						  "(%s datdba) AS dba, "
+						  "datdba, "
 						  "pg_encoding_to_char(encoding) AS encoding, "
 						  "datcollate, datctype, datfrozenxid, datminmxid, "
 						  "datacl, acldefault('d', datdba) AS acldefault, "
@@ -2780,13 +2791,12 @@ dumpDatabase(Archive *fout)
 						  "shobj_description(oid, 'pg_database') AS description "
 
 						  "FROM pg_database "
-						  "WHERE datname = current_database()",
-						  username_subquery);
+						  "WHERE datname = current_database()");
 	}
 	else
 	{
 		appendPQExpBuffer(dbQry, "SELECT tableoid, oid, datname, "
-						  "(%s datdba) AS dba, "
+						  "datdba, "
 						  "pg_encoding_to_char(encoding) AS encoding, "
 						  "datcollate, datctype, datfrozenxid, 0 AS datminmxid, "
 						  "datacl, acldefault('d', datdba) AS acldefault, "
@@ -2795,8 +2805,7 @@ dumpDatabase(Archive *fout)
 						  "shobj_description(oid, 'pg_database') AS description "
 
 						  "FROM pg_database "
-						  "WHERE datname = current_database()",
-						  username_subquery);
+						  "WHERE datname = current_database()");
 	}
 
 	res = ExecuteSqlQueryForSingleRow(fout, dbQry->data);
@@ -2804,7 +2813,7 @@ dumpDatabase(Archive *fout)
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_datname = PQfnumber(res, "datname");
-	i_dba = PQfnumber(res, "dba");
+	i_datdba = PQfnumber(res, "datdba");
 	i_encoding = PQfnumber(res, "encoding");
 	i_collate = PQfnumber(res, "datcollate");
 	i_ctype = PQfnumber(res, "datctype");
@@ -2819,7 +2828,7 @@ dumpDatabase(Archive *fout)
 	dbCatId.tableoid = atooid(PQgetvalue(res, 0, i_tableoid));
 	dbCatId.oid = atooid(PQgetvalue(res, 0, i_oid));
 	datname = PQgetvalue(res, 0, i_datname);
-	dba = PQgetvalue(res, 0, i_dba);
+	dba = getRoleName(PQgetvalue(res, 0, i_datdba));
 	encoding = PQgetvalue(res, 0, i_encoding);
 	collate = PQgetvalue(res, 0, i_collate);
 	ctype = PQgetvalue(res, 0, i_ctype);
@@ -3264,15 +3273,14 @@ getBlobs(Archive *fout)
 
 	/* Fetch BLOB OIDs, and owner/ACL data */
 	appendPQExpBuffer(blobQry,
-					  "SELECT oid, (%s lomowner) AS rolname, lomacl, "
+					  "SELECT oid, lomowner, lomacl, "
 					  "acldefault('L', lomowner) AS acldefault "
-					  "FROM pg_largeobject_metadata",
-					  username_subquery);
+					  "FROM pg_largeobject_metadata");
 
 	res = ExecuteSqlQuery(fout, blobQry->data, PGRES_TUPLES_OK);
 
 	i_oid = PQfnumber(res, "oid");
-	i_lomowner = PQfnumber(res, "rolname");
+	i_lomowner = PQfnumber(res, "lomowner");
 	i_lomacl = PQfnumber(res, "lomacl");
 	i_acldefault = PQfnumber(res, "acldefault");
 
@@ -3295,7 +3303,7 @@ getBlobs(Archive *fout)
 		binfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault));
 		binfo[i].dacl.privtype = 0;
 		binfo[i].dacl.initprivs = NULL;
-		binfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_lomowner));
+		binfo[i].rolname = getRoleName(PQgetvalue(res, i, i_lomowner));
 
 		/* Blobs have data */
 		binfo[i].dobj.components |= DUMP_COMPONENT_DATA;
@@ -3743,7 +3751,7 @@ getPublications(Archive *fout, int *numPublications)
 	int			i_tableoid;
 	int			i_oid;
 	int			i_pubname;
-	int			i_rolname;
+	int			i_pubowner;
 	int			i_puballtables;
 	int			i_pubinsert;
 	int			i_pubupdate;
@@ -3767,24 +3775,21 @@ getPublications(Archive *fout, int *numPublications)
 	if (fout->remoteVersion >= 130000)
 		appendPQExpBuffer(query,
 						  "SELECT p.tableoid, p.oid, p.pubname, "
-						  "(%s p.pubowner) AS rolname, "
+						  "p.pubowner, "
 						  "p.puballtables, p.pubinsert, p.pubupdate, p.pubdelete, p.pubtruncate, p.pubviaroot "
-						  "FROM pg_publication p",
-						  username_subquery);
+						  "FROM pg_publication p");
 	else if (fout->remoteVersion >= 110000)
 		appendPQExpBuffer(query,
 						  "SELECT p.tableoid, p.oid, p.pubname, "
-						  "(%s p.pubowner) AS rolname, "
+						  "p.pubowner, "
 						  "p.puballtables, p.pubinsert, p.pubupdate, p.pubdelete, p.pubtruncate, false AS pubviaroot "
-						  "FROM pg_publication p",
-						  username_subquery);
+						  "FROM pg_publication p");
 	else
 		appendPQExpBuffer(query,
 						  "SELECT p.tableoid, p.oid, p.pubname, "
-						  "(%s p.pubowner) AS rolname, "
+						  "p.pubowner, "
 						  "p.puballtables, p.pubinsert, p.pubupdate, p.pubdelete, false AS pubtruncate, false AS pubviaroot "
-						  "FROM pg_publication p",
-						  username_subquery);
+						  "FROM pg_publication p");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -3793,7 +3798,7 @@ getPublications(Archive *fout, int *numPublications)
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_pubname = PQfnumber(res, "pubname");
-	i_rolname = PQfnumber(res, "rolname");
+	i_pubowner = PQfnumber(res, "pubowner");
 	i_puballtables = PQfnumber(res, "puballtables");
 	i_pubinsert = PQfnumber(res, "pubinsert");
 	i_pubupdate = PQfnumber(res, "pubupdate");
@@ -3811,7 +3816,7 @@ getPublications(Archive *fout, int *numPublications)
 		pubinfo[i].dobj.catId.oid = atooid(PQgetvalue(res, i, i_oid));
 		AssignDumpId(&pubinfo[i].dobj);
 		pubinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_pubname));
-		pubinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		pubinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_pubowner));
 		pubinfo[i].puballtables =
 			(strcmp(PQgetvalue(res, i, i_puballtables), "t") == 0);
 		pubinfo[i].pubinsert =
@@ -3825,10 +3830,6 @@ getPublications(Archive *fout, int *numPublications)
 		pubinfo[i].pubviaroot =
 			(strcmp(PQgetvalue(res, i, i_pubviaroot), "t") == 0);
 
-		if (strlen(pubinfo[i].rolname) == 0)
-			pg_log_warning("owner of publication \"%s\" appears to be invalid",
-						   pubinfo[i].dobj.name);
-
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(pubinfo[i].dobj), fout);
 	}
@@ -4232,7 +4233,7 @@ getSubscriptions(Archive *fout)
 	int			i_tableoid;
 	int			i_oid;
 	int			i_subname;
-	int			i_rolname;
+	int			i_subowner;
 	int			i_substream;
 	int			i_subtwophasestate;
 	int			i_subconninfo;
@@ -4267,10 +4268,9 @@ getSubscriptions(Archive *fout)
 	/* Get the subscriptions in current database. */
 	appendPQExpBuffer(query,
 					  "SELECT s.tableoid, s.oid, s.subname,\n"
-					  " (%s s.subowner) AS rolname,\n"
+					  " s.subowner,\n"
 					  " s.subconninfo, s.subslotname, s.subsynccommit,\n"
-					  " s.subpublications,\n",
-					  username_subquery);
+					  " s.subpublications,\n");
 
 	if (fout->remoteVersion >= 140000)
 		appendPQExpBufferStr(query, " s.subbinary,\n");
@@ -4301,7 +4301,7 @@ getSubscriptions(Archive *fout)
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_subname = PQfnumber(res, "subname");
-	i_rolname = PQfnumber(res, "rolname");
+	i_subowner = PQfnumber(res, "subowner");
 	i_subconninfo = PQfnumber(res, "subconninfo");
 	i_subslotname = PQfnumber(res, "subslotname");
 	i_subsynccommit = PQfnumber(res, "subsynccommit");
@@ -4320,7 +4320,7 @@ getSubscriptions(Archive *fout)
 		subinfo[i].dobj.catId.oid = atooid(PQgetvalue(res, i, i_oid));
 		AssignDumpId(&subinfo[i].dobj);
 		subinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_subname));
-		subinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		subinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_subowner));
 		subinfo[i].subconninfo = pg_strdup(PQgetvalue(res, i, i_subconninfo));
 		if (PQgetisnull(res, i, i_subslotname))
 			subinfo[i].subslotname = NULL;
@@ -4337,10 +4337,6 @@ getSubscriptions(Archive *fout)
 		subinfo[i].subtwophasestate =
 			pg_strdup(PQgetvalue(res, i, i_subtwophasestate));
 
-		if (strlen(subinfo[i].rolname) == 0)
-			pg_log_warning("owner of subscription \"%s\" appears to be invalid",
-						   subinfo[i].dobj.name);
-
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(subinfo[i].dobj), fout);
 	}
@@ -4762,7 +4758,6 @@ getNamespaces(Archive *fout, int *numNamespaces)
 	int			i_oid;
 	int			i_nspname;
 	int			i_nspowner;
-	int			i_rolname;
 	int			i_nspacl;
 	int			i_acldefault;
 
@@ -4774,11 +4769,9 @@ getNamespaces(Archive *fout, int *numNamespaces)
 	 */
 	appendPQExpBuffer(query, "SELECT n.tableoid, n.oid, n.nspname, "
 					  "n.nspowner, "
-					  "(%s nspowner) AS rolname, "
 					  "n.nspacl, "
 					  "acldefault('n', n.nspowner) AS acldefault "
-					  "FROM pg_namespace n",
-					  username_subquery);
+					  "FROM pg_namespace n");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -4790,12 +4783,13 @@ getNamespaces(Archive *fout, int *numNamespaces)
 	i_oid = PQfnumber(res, "oid");
 	i_nspname = PQfnumber(res, "nspname");
 	i_nspowner = PQfnumber(res, "nspowner");
-	i_rolname = PQfnumber(res, "rolname");
 	i_nspacl = PQfnumber(res, "nspacl");
 	i_acldefault = PQfnumber(res, "acldefault");
 
 	for (i = 0; i < ntups; i++)
 	{
+		const char *nspowner;
+
 		nsinfo[i].dobj.objType = DO_NAMESPACE;
 		nsinfo[i].dobj.catId.tableoid = atooid(PQgetvalue(res, i, i_tableoid));
 		nsinfo[i].dobj.catId.oid = atooid(PQgetvalue(res, i, i_oid));
@@ -4805,8 +4799,9 @@ getNamespaces(Archive *fout, int *numNamespaces)
 		nsinfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault));
 		nsinfo[i].dacl.privtype = 0;
 		nsinfo[i].dacl.initprivs = NULL;
-		nsinfo[i].nspowner = atooid(PQgetvalue(res, i, i_nspowner));
-		nsinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		nspowner = PQgetvalue(res, i, i_nspowner);
+		nsinfo[i].nspowner = atooid(nspowner);
+		nsinfo[i].rolname = getRoleName(nspowner);
 
 		/* Decide whether to dump this namespace */
 		selectDumpableNamespace(&nsinfo[i], fout);
@@ -4855,10 +4850,6 @@ getNamespaces(Archive *fout, int *numNamespaces)
 			destroyPQExpBuffer(aclarray);
 			destroyPQExpBuffer(aclitem);
 		}
-
-		if (strlen(nsinfo[i].rolname) == 0)
-			pg_log_warning("owner of schema \"%s\" appears to be invalid",
-						   nsinfo[i].dobj.name);
 	}
 
 	PQclear(res);
@@ -4981,7 +4972,7 @@ getTypes(Archive *fout, int *numTypes)
 	int			i_typnamespace;
 	int			i_typacl;
 	int			i_acldefault;
-	int			i_rolname;
+	int			i_typowner;
 	int			i_typelem;
 	int			i_typrelid;
 	int			i_typrelkind;
@@ -5007,15 +4998,14 @@ getTypes(Archive *fout, int *numTypes)
 	appendPQExpBuffer(query, "SELECT tableoid, oid, typname, "
 					  "typnamespace, typacl, "
 					  "acldefault('T', typowner) AS acldefault, "
-					  "(%s typowner) AS rolname, "
+					  "typowner, "
 					  "typelem, typrelid, "
 					  "CASE WHEN typrelid = 0 THEN ' '::\"char\" "
 					  "ELSE (SELECT relkind FROM pg_class WHERE oid = typrelid) END AS typrelkind, "
 					  "typtype, typisdefined, "
 					  "typname[0] = '_' AND typelem != 0 AND "
 					  "(SELECT typarray FROM pg_type te WHERE oid = pg_type.typelem) = oid AS isarray "
-					  "FROM pg_type",
-					  username_subquery);
+					  "FROM pg_type");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5029,7 +5019,7 @@ getTypes(Archive *fout, int *numTypes)
 	i_typnamespace = PQfnumber(res, "typnamespace");
 	i_typacl = PQfnumber(res, "typacl");
 	i_acldefault = PQfnumber(res, "acldefault");
-	i_rolname = PQfnumber(res, "rolname");
+	i_typowner = PQfnumber(res, "typowner");
 	i_typelem = PQfnumber(res, "typelem");
 	i_typrelid = PQfnumber(res, "typrelid");
 	i_typrelkind = PQfnumber(res, "typrelkind");
@@ -5051,7 +5041,7 @@ getTypes(Archive *fout, int *numTypes)
 		tyinfo[i].dacl.privtype = 0;
 		tyinfo[i].dacl.initprivs = NULL;
 		tyinfo[i].ftypname = NULL;	/* may get filled later */
-		tyinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		tyinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_typowner));
 		tyinfo[i].typelem = atooid(PQgetvalue(res, i, i_typelem));
 		tyinfo[i].typrelid = atooid(PQgetvalue(res, i, i_typrelid));
 		tyinfo[i].typrelkind = *PQgetvalue(res, i, i_typrelkind);
@@ -5119,10 +5109,6 @@ getTypes(Archive *fout, int *numTypes)
 			 */
 			stinfo->dobj.dump = DUMP_COMPONENT_NONE;
 		}
-
-		if (strlen(tyinfo[i].rolname) == 0)
-			pg_log_warning("owner of data type \"%s\" appears to be invalid",
-						   tyinfo[i].dobj.name);
 	}
 
 	*numTypes = ntups;
@@ -5153,7 +5139,7 @@ getOperators(Archive *fout, int *numOprs)
 	int			i_oid;
 	int			i_oprname;
 	int			i_oprnamespace;
-	int			i_rolname;
+	int			i_oprowner;
 	int			i_oprkind;
 	int			i_oprcode;
 
@@ -5164,11 +5150,10 @@ getOperators(Archive *fout, int *numOprs)
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, oprname, "
 					  "oprnamespace, "
-					  "(%s oprowner) AS rolname, "
+					  "oprowner, "
 					  "oprkind, "
 					  "oprcode::oid AS oprcode "
-					  "FROM pg_operator",
-					  username_subquery);
+					  "FROM pg_operator");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5181,7 +5166,7 @@ getOperators(Archive *fout, int *numOprs)
 	i_oid = PQfnumber(res, "oid");
 	i_oprname = PQfnumber(res, "oprname");
 	i_oprnamespace = PQfnumber(res, "oprnamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_oprowner = PQfnumber(res, "oprowner");
 	i_oprkind = PQfnumber(res, "oprkind");
 	i_oprcode = PQfnumber(res, "oprcode");
 
@@ -5194,16 +5179,12 @@ getOperators(Archive *fout, int *numOprs)
 		oprinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_oprname));
 		oprinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_oprnamespace)));
-		oprinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		oprinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_oprowner));
 		oprinfo[i].oprkind = (PQgetvalue(res, i, i_oprkind))[0];
 		oprinfo[i].oprcode = atooid(PQgetvalue(res, i, i_oprcode));
 
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(oprinfo[i].dobj), fout);
-
-		if (strlen(oprinfo[i].rolname) == 0)
-			pg_log_warning("owner of operator \"%s\" appears to be invalid",
-						   oprinfo[i].dobj.name);
 	}
 
 	PQclear(res);
@@ -5232,7 +5213,7 @@ getCollations(Archive *fout, int *numCollations)
 	int			i_oid;
 	int			i_collname;
 	int			i_collnamespace;
-	int			i_rolname;
+	int			i_collowner;
 
 	query = createPQExpBuffer();
 
@@ -5243,9 +5224,8 @@ getCollations(Archive *fout, int *numCollations)
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, collname, "
 					  "collnamespace, "
-					  "(%s collowner) AS rolname "
-					  "FROM pg_collation",
-					  username_subquery);
+					  "collowner "
+					  "FROM pg_collation");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5258,7 +5238,7 @@ getCollations(Archive *fout, int *numCollations)
 	i_oid = PQfnumber(res, "oid");
 	i_collname = PQfnumber(res, "collname");
 	i_collnamespace = PQfnumber(res, "collnamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_collowner = PQfnumber(res, "collowner");
 
 	for (i = 0; i < ntups; i++)
 	{
@@ -5269,7 +5249,7 @@ getCollations(Archive *fout, int *numCollations)
 		collinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_collname));
 		collinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_collnamespace)));
-		collinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		collinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_collowner));
 
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(collinfo[i].dobj), fout);
@@ -5301,7 +5281,7 @@ getConversions(Archive *fout, int *numConversions)
 	int			i_oid;
 	int			i_conname;
 	int			i_connamespace;
-	int			i_rolname;
+	int			i_conowner;
 
 	query = createPQExpBuffer();
 
@@ -5312,9 +5292,8 @@ getConversions(Archive *fout, int *numConversions)
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, conname, "
 					  "connamespace, "
-					  "(%s conowner) AS rolname "
-					  "FROM pg_conversion",
-					  username_subquery);
+					  "conowner "
+					  "FROM pg_conversion");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5327,7 +5306,7 @@ getConversions(Archive *fout, int *numConversions)
 	i_oid = PQfnumber(res, "oid");
 	i_conname = PQfnumber(res, "conname");
 	i_connamespace = PQfnumber(res, "connamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_conowner = PQfnumber(res, "conowner");
 
 	for (i = 0; i < ntups; i++)
 	{
@@ -5338,7 +5317,7 @@ getConversions(Archive *fout, int *numConversions)
 		convinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_conname));
 		convinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_connamespace)));
-		convinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		convinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_conowner));
 
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(convinfo[i].dobj), fout);
@@ -5441,7 +5420,7 @@ getOpclasses(Archive *fout, int *numOpclasses)
 	int			i_oid;
 	int			i_opcname;
 	int			i_opcnamespace;
-	int			i_rolname;
+	int			i_opcowner;
 
 	/*
 	 * find all opclasses, including builtin opclasses; we filter out
@@ -5450,9 +5429,8 @@ getOpclasses(Archive *fout, int *numOpclasses)
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, opcname, "
 					  "opcnamespace, "
-					  "(%s opcowner) AS rolname "
-					  "FROM pg_opclass",
-					  username_subquery);
+					  "opcowner "
+					  "FROM pg_opclass");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5465,7 +5443,7 @@ getOpclasses(Archive *fout, int *numOpclasses)
 	i_oid = PQfnumber(res, "oid");
 	i_opcname = PQfnumber(res, "opcname");
 	i_opcnamespace = PQfnumber(res, "opcnamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_opcowner = PQfnumber(res, "opcowner");
 
 	for (i = 0; i < ntups; i++)
 	{
@@ -5476,14 +5454,10 @@ getOpclasses(Archive *fout, int *numOpclasses)
 		opcinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_opcname));
 		opcinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_opcnamespace)));
-		opcinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		opcinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_opcowner));
 
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(opcinfo[i].dobj), fout);
-
-		if (strlen(opcinfo[i].rolname) == 0)
-			pg_log_warning("owner of operator class \"%s\" appears to be invalid",
-						   opcinfo[i].dobj.name);
 	}
 
 	PQclear(res);
@@ -5512,7 +5486,7 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 	int			i_oid;
 	int			i_opfname;
 	int			i_opfnamespace;
-	int			i_rolname;
+	int			i_opfowner;
 
 	query = createPQExpBuffer();
 
@@ -5523,9 +5497,8 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, opfname, "
 					  "opfnamespace, "
-					  "(%s opfowner) AS rolname "
-					  "FROM pg_opfamily",
-					  username_subquery);
+					  "opfowner "
+					  "FROM pg_opfamily");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5538,7 +5511,7 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 	i_oid = PQfnumber(res, "oid");
 	i_opfname = PQfnumber(res, "opfname");
 	i_opfnamespace = PQfnumber(res, "opfnamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_opfowner = PQfnumber(res, "opfowner");
 
 	for (i = 0; i < ntups; i++)
 	{
@@ -5549,14 +5522,10 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 		opfinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_opfname));
 		opfinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_opfnamespace)));
-		opfinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		opfinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_opfowner));
 
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(opfinfo[i].dobj), fout);
-
-		if (strlen(opfinfo[i].rolname) == 0)
-			pg_log_warning("owner of operator family \"%s\" appears to be invalid",
-						   opfinfo[i].dobj.name);
 	}
 
 	PQclear(res);
@@ -5588,7 +5557,7 @@ getAggregates(Archive *fout, int *numAggs)
 	int			i_aggnamespace;
 	int			i_pronargs;
 	int			i_proargtypes;
-	int			i_rolname;
+	int			i_proowner;
 	int			i_aggacl;
 	int			i_acldefault;
 
@@ -5607,7 +5576,7 @@ getAggregates(Archive *fout, int *numAggs)
 						  "p.proname AS aggname, "
 						  "p.pronamespace AS aggnamespace, "
 						  "p.pronargs, p.proargtypes, "
-						  "(%s p.proowner) AS rolname, "
+						  "p.proowner, "
 						  "p.proacl AS aggacl, "
 						  "acldefault('f', p.proowner) AS acldefault "
 						  "FROM pg_proc p "
@@ -5620,7 +5589,6 @@ getAggregates(Archive *fout, int *numAggs)
 						  "(SELECT oid FROM pg_namespace "
 						  "WHERE nspname = 'pg_catalog') OR "
 						  "p.proacl IS DISTINCT FROM pip.initprivs",
-						  username_subquery,
 						  agg_check);
 		if (dopt->binary_upgrade)
 			appendPQExpBufferStr(query,
@@ -5636,15 +5604,14 @@ getAggregates(Archive *fout, int *numAggs)
 		appendPQExpBuffer(query, "SELECT tableoid, oid, proname AS aggname, "
 						  "pronamespace AS aggnamespace, "
 						  "pronargs, proargtypes, "
-						  "(%s proowner) AS rolname, "
+						  "proowner, "
 						  "proacl AS aggacl, "
 						  "acldefault('f', proowner) AS acldefault "
 						  "FROM pg_proc p "
 						  "WHERE proisagg AND ("
 						  "pronamespace != "
 						  "(SELECT oid FROM pg_namespace "
-						  "WHERE nspname = 'pg_catalog')",
-						  username_subquery);
+						  "WHERE nspname = 'pg_catalog')");
 		if (dopt->binary_upgrade)
 			appendPQExpBufferStr(query,
 								 " OR EXISTS(SELECT 1 FROM pg_depend WHERE "
@@ -5668,7 +5635,7 @@ getAggregates(Archive *fout, int *numAggs)
 	i_aggnamespace = PQfnumber(res, "aggnamespace");
 	i_pronargs = PQfnumber(res, "pronargs");
 	i_proargtypes = PQfnumber(res, "proargtypes");
-	i_rolname = PQfnumber(res, "rolname");
+	i_proowner = PQfnumber(res, "proowner");
 	i_aggacl = PQfnumber(res, "aggacl");
 	i_acldefault = PQfnumber(res, "acldefault");
 
@@ -5685,10 +5652,7 @@ getAggregates(Archive *fout, int *numAggs)
 		agginfo[i].aggfn.dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault));
 		agginfo[i].aggfn.dacl.privtype = 0;
 		agginfo[i].aggfn.dacl.initprivs = NULL;
-		agginfo[i].aggfn.rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
-		if (strlen(agginfo[i].aggfn.rolname) == 0)
-			pg_log_warning("owner of aggregate function \"%s\" appears to be invalid",
-						   agginfo[i].aggfn.dobj.name);
+		agginfo[i].aggfn.rolname = getRoleName(PQgetvalue(res, i, i_proowner));
 		agginfo[i].aggfn.lang = InvalidOid; /* not currently interesting */
 		agginfo[i].aggfn.prorettype = InvalidOid;	/* not saved */
 		agginfo[i].aggfn.nargs = atoi(PQgetvalue(res, i, i_pronargs));
@@ -5737,7 +5701,7 @@ getFuncs(Archive *fout, int *numFuncs)
 	int			i_oid;
 	int			i_proname;
 	int			i_pronamespace;
-	int			i_rolname;
+	int			i_proowner;
 	int			i_prolang;
 	int			i_pronargs;
 	int			i_proargtypes;
@@ -5779,7 +5743,7 @@ getFuncs(Archive *fout, int *numFuncs)
 						  "p.proacl, "
 						  "acldefault('f', p.proowner) AS acldefault, "
 						  "p.pronamespace, "
-						  "(%s p.proowner) AS rolname "
+						  "p.proowner "
 						  "FROM pg_proc p "
 						  "LEFT JOIN pg_init_privs pip ON "
 						  "(p.oid = pip.objoid "
@@ -5800,7 +5764,6 @@ getFuncs(Archive *fout, int *numFuncs)
 						  "\n  WHERE pg_transform.oid > %u AND "
 						  "\n  (p.oid = pg_transform.trffromsql"
 						  "\n  OR p.oid = pg_transform.trftosql))",
-						  username_subquery,
 						  not_agg_check,
 						  g_last_builtin_oid,
 						  g_last_builtin_oid);
@@ -5822,7 +5785,7 @@ getFuncs(Archive *fout, int *numFuncs)
 						  "pronargs, proargtypes, prorettype, proacl, "
 						  "acldefault('f', proowner) AS acldefault, "
 						  "pronamespace, "
-						  "(%s proowner) AS rolname "
+						  "proowner "
 						  "FROM pg_proc p "
 						  "WHERE NOT proisagg"
 						  "\n  AND NOT EXISTS (SELECT 1 FROM pg_depend "
@@ -5835,7 +5798,6 @@ getFuncs(Archive *fout, int *numFuncs)
 						  "\n  OR EXISTS (SELECT 1 FROM pg_cast"
 						  "\n  WHERE pg_cast.oid > '%u'::oid"
 						  "\n  AND p.oid = pg_cast.castfunc)",
-						  username_subquery,
 						  g_last_builtin_oid);
 
 		if (fout->remoteVersion >= 90500)
@@ -5868,7 +5830,7 @@ getFuncs(Archive *fout, int *numFuncs)
 	i_oid = PQfnumber(res, "oid");
 	i_proname = PQfnumber(res, "proname");
 	i_pronamespace = PQfnumber(res, "pronamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_proowner = PQfnumber(res, "proowner");
 	i_prolang = PQfnumber(res, "prolang");
 	i_pronargs = PQfnumber(res, "pronargs");
 	i_proargtypes = PQfnumber(res, "proargtypes");
@@ -5889,7 +5851,7 @@ getFuncs(Archive *fout, int *numFuncs)
 		finfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault));
 		finfo[i].dacl.privtype = 0;
 		finfo[i].dacl.initprivs = NULL;
-		finfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		finfo[i].rolname = getRoleName(PQgetvalue(res, i, i_proowner));
 		finfo[i].lang = atooid(PQgetvalue(res, i, i_prolang));
 		finfo[i].prorettype = atooid(PQgetvalue(res, i, i_prorettype));
 		finfo[i].nargs = atoi(PQgetvalue(res, i, i_pronargs));
@@ -5908,10 +5870,6 @@ getFuncs(Archive *fout, int *numFuncs)
 		/* Mark whether function has an ACL */
 		if (!PQgetisnull(res, i, i_proacl))
 			finfo[i].dobj.components |= DUMP_COMPONENT_ACL;
-
-		if (strlen(finfo[i].rolname) == 0)
-			pg_log_warning("owner of function \"%s\" appears to be invalid",
-						   finfo[i].dobj.name);
 	}
 
 	PQclear(res);
@@ -5943,7 +5901,7 @@ getTables(Archive *fout, int *numTables)
 	int			i_relnamespace;
 	int			i_relkind;
 	int			i_reltype;
-	int			i_rolname;
+	int			i_relowner;
 	int			i_relchecks;
 	int			i_relhasindex;
 	int			i_relhasrules;
@@ -5995,7 +5953,7 @@ getTables(Archive *fout, int *numTables)
 	appendPQExpBuffer(query,
 					  "SELECT c.tableoid, c.oid, c.relname, "
 					  "c.relnamespace, c.relkind, c.reltype, "
-					  "(%s c.relowner) AS rolname, "
+					  "c.relowner, "
 					  "c.relchecks, "
 					  "c.relhasindex, c.relhasrules, c.relpages, "
 					  "c.relhastriggers, "
@@ -6013,8 +5971,7 @@ getTables(Archive *fout, int *numTables)
 					  "tc.reloptions AS toast_reloptions, "
 					  "d.refobjid AS owning_tab, "
 					  "d.refobjsubid AS owning_col, "
-					  "tsp.spcname AS reltablespace, ",
-					  username_subquery);
+					  "tsp.spcname AS reltablespace, ");
 
 	if (fout->remoteVersion >= 120000)
 		appendPQExpBufferStr(query,
@@ -6070,12 +6027,7 @@ getTables(Archive *fout, int *numTables)
 
 	if (fout->remoteVersion >= 90600)
 		appendPQExpBufferStr(query,
-							 "c.relkind = " CppAsString2(RELKIND_SEQUENCE)
-							 " AND EXISTS (SELECT 1 FROM pg_depend "
-							 "WHERE classid = 'pg_class'::regclass AND "
-							 "objid = c.oid AND objsubid = 0 AND "
-							 "refclassid = 'pg_class'::regclass AND "
-							 "deptype = 'i') AS is_identity_sequence, ");
+							 "(d.deptype = 'i') IS TRUE AS is_identity_sequence, ");
 	else
 		appendPQExpBufferStr(query,
 							 "false AS is_identity_sequence, ");
@@ -6163,7 +6115,7 @@ getTables(Archive *fout, int *numTables)
 	i_relnamespace = PQfnumber(res, "relnamespace");
 	i_relkind = PQfnumber(res, "relkind");
 	i_reltype = PQfnumber(res, "reltype");
-	i_rolname = PQfnumber(res, "rolname");
+	i_relowner = PQfnumber(res, "relowner");
 	i_relchecks = PQfnumber(res, "relchecks");
 	i_relhasindex = PQfnumber(res, "relhasindex");
 	i_relhasrules = PQfnumber(res, "relhasrules");
@@ -6225,7 +6177,7 @@ getTables(Archive *fout, int *numTables)
 		tblinfo[i].dacl.initprivs = NULL;
 		tblinfo[i].relkind = *(PQgetvalue(res, i, i_relkind));
 		tblinfo[i].reltype = atooid(PQgetvalue(res, i, i_reltype));
-		tblinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		tblinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_relowner));
 		tblinfo[i].ncheck = atoi(PQgetvalue(res, i, i_relchecks));
 		tblinfo[i].hasindex = (strcmp(PQgetvalue(res, i, i_relhasindex), "t") == 0);
 		tblinfo[i].hasrules = (strcmp(PQgetvalue(res, i, i_relhasrules), "t") == 0);
@@ -6333,11 +6285,6 @@ getTables(Archive *fout, int *numTables)
 							  fmtQualifiedDumpable(&tblinfo[i]));
 			ExecuteSqlStatement(fout, query->data);
 		}
-
-		/* Emit notice if join for owner failed */
-		if (strlen(tblinfo[i].rolname) == 0)
-			pg_log_warning("owner of table \"%s\" appears to be invalid",
-						   tblinfo[i].dobj.name);
 	}
 
 	if (dopt->lockWaitTimeout)
@@ -6781,7 +6728,7 @@ getExtendedStatistics(Archive *fout)
 	int			i_oid;
 	int			i_stxname;
 	int			i_stxnamespace;
-	int			i_rolname;
+	int			i_stxowner;
 	int			i_stattarget;
 	int			i;
 
@@ -6793,14 +6740,12 @@ getExtendedStatistics(Archive *fout)
 
 	if (fout->remoteVersion < 130000)
 		appendPQExpBuffer(query, "SELECT tableoid, oid, stxname, "
-						  "stxnamespace, (%s stxowner) AS rolname, (-1) AS stxstattarget "
-						  "FROM pg_catalog.pg_statistic_ext",
-						  username_subquery);
+						  "stxnamespace, stxowner, (-1) AS stxstattarget "
+						  "FROM pg_catalog.pg_statistic_ext");
 	else
 		appendPQExpBuffer(query, "SELECT tableoid, oid, stxname, "
-						  "stxnamespace, (%s stxowner) AS rolname, stxstattarget "
-						  "FROM pg_catalog.pg_statistic_ext",
-						  username_subquery);
+						  "stxnamespace, stxowner, stxstattarget "
+						  "FROM pg_catalog.pg_statistic_ext");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -6810,7 +6755,7 @@ getExtendedStatistics(Archive *fout)
 	i_oid = PQfnumber(res, "oid");
 	i_stxname = PQfnumber(res, "stxname");
 	i_stxnamespace = PQfnumber(res, "stxnamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_stxowner = PQfnumber(res, "stxowner");
 	i_stattarget = PQfnumber(res, "stxstattarget");
 
 	statsextinfo = (StatsExtInfo *) pg_malloc(ntups * sizeof(StatsExtInfo));
@@ -6824,7 +6769,7 @@ getExtendedStatistics(Archive *fout)
 		statsextinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_stxname));
 		statsextinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_stxnamespace)));
-		statsextinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		statsextinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_stxowner));
 		statsextinfo[i].stattarget = atoi(PQgetvalue(res, i, i_stattarget));
 
 		/* Decide whether we want to dump it */
@@ -7499,14 +7444,13 @@ getEventTriggers(Archive *fout, int *numEventTriggers)
 
 	appendPQExpBuffer(query,
 					  "SELECT e.tableoid, e.oid, evtname, evtenabled, "
-					  "evtevent, (%s evtowner) AS evtowner, "
+					  "evtevent, evtowner, "
 					  "array_to_string(array("
 					  "select quote_literal(x) "
 					  " from unnest(evttags) as t(x)), ', ') as evttags, "
 					  "e.evtfoid::regproc as evtfname "
 					  "FROM pg_event_trigger e "
-					  "ORDER BY e.oid",
-					  username_subquery);
+					  "ORDER BY e.oid");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -7534,7 +7478,7 @@ getEventTriggers(Archive *fout, int *numEventTriggers)
 		evtinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_evtname));
 		evtinfo[i].evtname = pg_strdup(PQgetvalue(res, i, i_evtname));
 		evtinfo[i].evtevent = pg_strdup(PQgetvalue(res, i, i_evtevent));
-		evtinfo[i].evtowner = pg_strdup(PQgetvalue(res, i, i_evtowner));
+		evtinfo[i].evtowner = getRoleName(PQgetvalue(res, i, i_evtowner));
 		evtinfo[i].evttags = pg_strdup(PQgetvalue(res, i, i_evttags));
 		evtinfo[i].evtfname = pg_strdup(PQgetvalue(res, i, i_evtfname));
 		evtinfo[i].evtenabled = *(PQgetvalue(res, i, i_evtenabled));
@@ -7583,11 +7527,10 @@ getProcLangs(Archive *fout, int *numProcLangs)
 					  "laninline, lanvalidator, "
 					  "lanacl, "
 					  "acldefault('l', lanowner) AS acldefault, "
-					  "(%s lanowner) AS lanowner "
+					  "lanowner "
 					  "FROM pg_language "
 					  "WHERE lanispl "
-					  "ORDER BY oid",
-					  username_subquery);
+					  "ORDER BY oid");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -7624,7 +7567,7 @@ getProcLangs(Archive *fout, int *numProcLangs)
 		planginfo[i].lanplcallfoid = atooid(PQgetvalue(res, i, i_lanplcallfoid));
 		planginfo[i].laninline = atooid(PQgetvalue(res, i, i_laninline));
 		planginfo[i].lanvalidator = atooid(PQgetvalue(res, i, i_lanvalidator));
-		planginfo[i].lanowner = pg_strdup(PQgetvalue(res, i, i_lanowner));
+		planginfo[i].lanowner = getRoleName(PQgetvalue(res, i, i_lanowner));
 
 		/* Decide whether we want to dump it */
 		selectDumpableProcLang(&(planginfo[i]), fout);
@@ -8532,17 +8475,16 @@ getTSDictionaries(Archive *fout, int *numTSDicts)
 	int			i_oid;
 	int			i_dictname;
 	int			i_dictnamespace;
-	int			i_rolname;
+	int			i_dictowner;
 	int			i_dicttemplate;
 	int			i_dictinitoption;
 
 	query = createPQExpBuffer();
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, dictname, "
-					  "dictnamespace, (%s dictowner) AS rolname, "
+					  "dictnamespace, dictowner, "
 					  "dicttemplate, dictinitoption "
-					  "FROM pg_ts_dict",
-					  username_subquery);
+					  "FROM pg_ts_dict");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -8555,7 +8497,7 @@ getTSDictionaries(Archive *fout, int *numTSDicts)
 	i_oid = PQfnumber(res, "oid");
 	i_dictname = PQfnumber(res, "dictname");
 	i_dictnamespace = PQfnumber(res, "dictnamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_dictowner = PQfnumber(res, "dictowner");
 	i_dictinitoption = PQfnumber(res, "dictinitoption");
 	i_dicttemplate = PQfnumber(res, "dicttemplate");
 
@@ -8568,7 +8510,7 @@ getTSDictionaries(Archive *fout, int *numTSDicts)
 		dictinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_dictname));
 		dictinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_dictnamespace)));
-		dictinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		dictinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_dictowner));
 		dictinfo[i].dicttemplate = atooid(PQgetvalue(res, i, i_dicttemplate));
 		if (PQgetisnull(res, i, i_dictinitoption))
 			dictinfo[i].dictinitoption = NULL;
@@ -8670,15 +8612,14 @@ getTSConfigurations(Archive *fout, int *numTSConfigs)
 	int			i_oid;
 	int			i_cfgname;
 	int			i_cfgnamespace;
-	int			i_rolname;
+	int			i_cfgowner;
 	int			i_cfgparser;
 
 	query = createPQExpBuffer();
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, cfgname, "
-					  "cfgnamespace, (%s cfgowner) AS rolname, cfgparser "
-					  "FROM pg_ts_config",
-					  username_subquery);
+					  "cfgnamespace, cfgowner, cfgparser "
+					  "FROM pg_ts_config");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -8691,7 +8632,7 @@ getTSConfigurations(Archive *fout, int *numTSConfigs)
 	i_oid = PQfnumber(res, "oid");
 	i_cfgname = PQfnumber(res, "cfgname");
 	i_cfgnamespace = PQfnumber(res, "cfgnamespace");
-	i_rolname = PQfnumber(res, "rolname");
+	i_cfgowner = PQfnumber(res, "cfgowner");
 	i_cfgparser = PQfnumber(res, "cfgparser");
 
 	for (i = 0; i < ntups; i++)
@@ -8703,7 +8644,7 @@ getTSConfigurations(Archive *fout, int *numTSConfigs)
 		cfginfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_cfgname));
 		cfginfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_cfgnamespace)));
-		cfginfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		cfginfo[i].rolname = getRoleName(PQgetvalue(res, i, i_cfgowner));
 		cfginfo[i].cfgparser = atooid(PQgetvalue(res, i, i_cfgparser));
 
 		/* Decide whether we want to dump it */
@@ -8735,7 +8676,7 @@ getForeignDataWrappers(Archive *fout, int *numForeignDataWrappers)
 	int			i_tableoid;
 	int			i_oid;
 	int			i_fdwname;
-	int			i_rolname;
+	int			i_fdwowner;
 	int			i_fdwhandler;
 	int			i_fdwvalidator;
 	int			i_fdwacl;
@@ -8745,7 +8686,7 @@ getForeignDataWrappers(Archive *fout, int *numForeignDataWrappers)
 	query = createPQExpBuffer();
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, fdwname, "
-					  "(%s fdwowner) AS rolname, "
+					  "fdwowner, "
 					  "fdwhandler::pg_catalog.regproc, "
 					  "fdwvalidator::pg_catalog.regproc, "
 					  "fdwacl, "
@@ -8756,8 +8697,7 @@ getForeignDataWrappers(Archive *fout, int *numForeignDataWrappers)
 					  "FROM pg_options_to_table(fdwoptions) "
 					  "ORDER BY option_name"
 					  "), E',\n    ') AS fdwoptions "
-					  "FROM pg_foreign_data_wrapper",
-					  username_subquery);
+					  "FROM pg_foreign_data_wrapper");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -8769,7 +8709,7 @@ getForeignDataWrappers(Archive *fout, int *numForeignDataWrappers)
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_fdwname = PQfnumber(res, "fdwname");
-	i_rolname = PQfnumber(res, "rolname");
+	i_fdwowner = PQfnumber(res, "fdwowner");
 	i_fdwhandler = PQfnumber(res, "fdwhandler");
 	i_fdwvalidator = PQfnumber(res, "fdwvalidator");
 	i_fdwacl = PQfnumber(res, "fdwacl");
@@ -8788,7 +8728,7 @@ getForeignDataWrappers(Archive *fout, int *numForeignDataWrappers)
 		fdwinfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault));
 		fdwinfo[i].dacl.privtype = 0;
 		fdwinfo[i].dacl.initprivs = NULL;
-		fdwinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		fdwinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_fdwowner));
 		fdwinfo[i].fdwhandler = pg_strdup(PQgetvalue(res, i, i_fdwhandler));
 		fdwinfo[i].fdwvalidator = pg_strdup(PQgetvalue(res, i, i_fdwvalidator));
 		fdwinfo[i].fdwoptions = pg_strdup(PQgetvalue(res, i, i_fdwoptions));
@@ -8826,7 +8766,7 @@ getForeignServers(Archive *fout, int *numForeignServers)
 	int			i_tableoid;
 	int			i_oid;
 	int			i_srvname;
-	int			i_rolname;
+	int			i_srvowner;
 	int			i_srvfdw;
 	int			i_srvtype;
 	int			i_srvversion;
@@ -8837,7 +8777,7 @@ getForeignServers(Archive *fout, int *numForeignServers)
 	query = createPQExpBuffer();
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, srvname, "
-					  "(%s srvowner) AS rolname, "
+					  "srvowner, "
 					  "srvfdw, srvtype, srvversion, srvacl, "
 					  "acldefault('S', srvowner) AS acldefault, "
 					  "array_to_string(ARRAY("
@@ -8846,8 +8786,7 @@ getForeignServers(Archive *fout, int *numForeignServers)
 					  "FROM pg_options_to_table(srvoptions) "
 					  "ORDER BY option_name"
 					  "), E',\n    ') AS srvoptions "
-					  "FROM pg_foreign_server",
-					  username_subquery);
+					  "FROM pg_foreign_server");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -8859,7 +8798,7 @@ getForeignServers(Archive *fout, int *numForeignServers)
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_srvname = PQfnumber(res, "srvname");
-	i_rolname = PQfnumber(res, "rolname");
+	i_srvowner = PQfnumber(res, "srvowner");
 	i_srvfdw = PQfnumber(res, "srvfdw");
 	i_srvtype = PQfnumber(res, "srvtype");
 	i_srvversion = PQfnumber(res, "srvversion");
@@ -8879,7 +8818,7 @@ getForeignServers(Archive *fout, int *numForeignServers)
 		srvinfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault));
 		srvinfo[i].dacl.privtype = 0;
 		srvinfo[i].dacl.initprivs = NULL;
-		srvinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		srvinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_srvowner));
 		srvinfo[i].srvfdw = atooid(PQgetvalue(res, i, i_srvfdw));
 		srvinfo[i].srvtype = pg_strdup(PQgetvalue(res, i, i_srvtype));
 		srvinfo[i].srvversion = pg_strdup(PQgetvalue(res, i, i_srvversion));
@@ -8943,7 +8882,7 @@ getDefaultACLs(Archive *fout, int *numDefaultACLs)
 	 */
 	appendPQExpBuffer(query,
 					  "SELECT oid, tableoid, "
-					  "(%s defaclrole) AS defaclrole, "
+					  "defaclrole, "
 					  "defaclnamespace, "
 					  "defaclobjtype, "
 					  "defaclacl, "
@@ -8951,8 +8890,7 @@ getDefaultACLs(Archive *fout, int *numDefaultACLs)
 					  "acldefault(CASE WHEN defaclobjtype = 'S' "
 					  "THEN 's'::\"char\" ELSE defaclobjtype END, "
 					  "defaclrole) ELSE '{}' END AS acldefault "
-					  "FROM pg_default_acl",
-					  username_subquery);
+					  "FROM pg_default_acl");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -8989,7 +8927,7 @@ getDefaultACLs(Archive *fout, int *numDefaultACLs)
 		daclinfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault));
 		daclinfo[i].dacl.privtype = 0;
 		daclinfo[i].dacl.initprivs = NULL;
-		daclinfo[i].defaclrole = pg_strdup(PQgetvalue(res, i, i_defaclrole));
+		daclinfo[i].defaclrole = getRoleName(PQgetvalue(res, i, i_defaclrole));
 		daclinfo[i].defaclobjtype = *(PQgetvalue(res, i, i_defaclobjtype));
 
 		/* Default ACLs are ACLs, of course */
@@ -9007,6 +8945,71 @@ getDefaultACLs(Archive *fout, int *numDefaultACLs)
 }
 
 /*
+ * getRoleName -- look up the name of a role, given its OID
+ *
+ * In current usage, we don't expect failures, so error out for a bad OID.
+ */
+static const char *
+getRoleName(const char *roleoid_str)
+{
+	Oid			roleoid = atooid(roleoid_str);
+
+	/*
+	 * Do binary search to find the appropriate item.
+	 */
+	if (nrolenames > 0)
+	{
+		RoleNameItem *low = &rolenames[0];
+		RoleNameItem *high = &rolenames[nrolenames - 1];
+
+		while (low <= high)
+		{
+			RoleNameItem *middle = low + (high - low) / 2;
+
+			if (roleoid < middle->roleoid)
+				high = middle - 1;
+			else if (roleoid > middle->roleoid)
+				low = middle + 1;
+			else
+				return middle->rolename;	/* found a match */
+		}
+	}
+
+	fatal("role with OID %u does not exist", roleoid);
+	return NULL;				/* keep compiler quiet */
+}
+
+/*
+ * collectRoleNames --
+ *
+ * Construct a table of all known roles.
+ * The table is sorted by OID for speed in lookup.
+ */
+static void
+collectRoleNames(Archive *fout)
+{
+	PGresult   *res;
+	const char *query;
+	int			i;
+
+	query = "SELECT oid, rolname FROM pg_catalog.pg_roles ORDER BY 1";
+
+	res = ExecuteSqlQuery(fout, query, PGRES_TUPLES_OK);
+
+	nrolenames = PQntuples(res);
+
+	rolenames = (RoleNameItem *) pg_malloc(nrolenames * sizeof(RoleNameItem));
+
+	for (i = 0; i < nrolenames; i++)
+	{
+		rolenames[i].roleoid = atooid(PQgetvalue(res, i, 0));
+		rolenames[i].rolename = pg_strdup(PQgetvalue(res, i, 1));
+	}
+
+	PQclear(res);
+}
+
+/*
  * getAdditionalACLs
  *
  * We have now created all the DumpableObjects, and collected the ACL data
diff --git a/src/bin/pg_dump/pg_dump.h b/src/bin/pg_dump/pg_dump.h
index f011ace8a8..f9deb321ac 100644
--- a/src/bin/pg_dump/pg_dump.h
+++ b/src/bin/pg_dump/pg_dump.h
@@ -171,8 +171,8 @@ typedef struct _namespaceInfo
 	DumpableObject dobj;
 	DumpableAcl dacl;
 	bool		create;			/* CREATE SCHEMA, or just set owner? */
-	Oid			nspowner;
-	char	   *rolname;		/* name of owner, or empty string */
+	Oid			nspowner;		/* OID of owner */
+	const char *rolname;		/* name of owner */
 } NamespaceInfo;
 
 typedef struct _extensionInfo
@@ -196,7 +196,7 @@ typedef struct _typeInfo
 	 * schema-qualified too.
 	 */
 	char	   *ftypname;
-	char	   *rolname;		/* name of owner, or empty string */
+	const char *rolname;
 	Oid			typelem;
 	Oid			typrelid;
 	char		typrelkind;		/* 'r', 'v', 'c', etc */
@@ -222,7 +222,7 @@ typedef struct _funcInfo
 {
 	DumpableObject dobj;
 	DumpableAcl dacl;
-	char	   *rolname;		/* name of owner, or empty string */
+	const char *rolname;
 	Oid			lang;
 	int			nargs;
 	Oid		   *argtypes;
@@ -239,7 +239,7 @@ typedef struct _aggInfo
 typedef struct _oprInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 	char		oprkind;
 	Oid			oprcode;
 } OprInfo;
@@ -254,25 +254,25 @@ typedef struct _accessMethodInfo
 typedef struct _opclassInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 } OpclassInfo;
 
 typedef struct _opfamilyInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 } OpfamilyInfo;
 
 typedef struct _collInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 } CollInfo;
 
 typedef struct _convInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 } ConvInfo;
 
 typedef struct _tableInfo
@@ -282,7 +282,7 @@ typedef struct _tableInfo
 	 */
 	DumpableObject dobj;
 	DumpableAcl dacl;
-	char	   *rolname;		/* name of owner, or empty string */
+	const char *rolname;
 	char		relkind;
 	char		relpersistence; /* relation persistence */
 	bool		relispopulated; /* relation is populated */
@@ -415,7 +415,7 @@ typedef struct _indexAttachInfo
 typedef struct _statsExtInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;		/* name of owner, or empty string */
+	const char *rolname;
 	int			stattarget;		/* statistics target */
 } StatsExtInfo;
 
@@ -454,7 +454,7 @@ typedef struct _evttriggerInfo
 	DumpableObject dobj;
 	char	   *evtname;
 	char	   *evtevent;
-	char	   *evtowner;
+	const char *evtowner;
 	char	   *evttags;
 	char	   *evtfname;
 	char		evtenabled;
@@ -491,7 +491,7 @@ typedef struct _procLangInfo
 	Oid			lanplcallfoid;
 	Oid			laninline;
 	Oid			lanvalidator;
-	char	   *lanowner;		/* name of owner, or empty string */
+	const char *lanowner;
 } ProcLangInfo;
 
 typedef struct _castInfo
@@ -533,7 +533,7 @@ typedef struct _prsInfo
 typedef struct _dictInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 	Oid			dicttemplate;
 	char	   *dictinitoption;
 } TSDictInfo;
@@ -548,7 +548,7 @@ typedef struct _tmplInfo
 typedef struct _cfgInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 	Oid			cfgparser;
 } TSConfigInfo;
 
@@ -556,7 +556,7 @@ typedef struct _fdwInfo
 {
 	DumpableObject dobj;
 	DumpableAcl dacl;
-	char	   *rolname;
+	const char *rolname;
 	char	   *fdwhandler;
 	char	   *fdwvalidator;
 	char	   *fdwoptions;
@@ -566,7 +566,7 @@ typedef struct _foreignServerInfo
 {
 	DumpableObject dobj;
 	DumpableAcl dacl;
-	char	   *rolname;
+	const char *rolname;
 	Oid			srvfdw;
 	char	   *srvtype;
 	char	   *srvversion;
@@ -577,7 +577,7 @@ typedef struct _defaultACLInfo
 {
 	DumpableObject dobj;
 	DumpableAcl dacl;
-	char	   *defaclrole;
+	const char *defaclrole;
 	char		defaclobjtype;
 } DefaultACLInfo;
 
@@ -585,7 +585,7 @@ typedef struct _blobInfo
 {
 	DumpableObject dobj;
 	DumpableAcl dacl;
-	char	   *rolname;
+	const char *rolname;
 } BlobInfo;
 
 /*
@@ -612,7 +612,7 @@ typedef struct _policyInfo
 typedef struct _PublicationInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 	bool		puballtables;
 	bool		pubinsert;
 	bool		pubupdate;
@@ -649,7 +649,7 @@ typedef struct _PublicationSchemaInfo
 typedef struct _SubscriptionInfo
 {
 	DumpableObject dobj;
-	char	   *rolname;
+	const char *rolname;
 	char	   *subconninfo;
 	char	   *subslotname;
 	char	   *subbinary;