Sort dump objects independent of OIDs, for the 7 holdout object types.

pg_dump sorts objects by their logical names, e.g. (nspname, relname,
tgname), before dependency-driven reordering.  That removes one source
of logically-identical databases differing in their schema-only dumps.
In other words, it helps with schema diffing.  The logical name sort
ignored essential sort keys for constraints, operators, PUBLICATION
... FOR TABLE, PUBLICATION ... FOR TABLES IN SCHEMA, operator classes,
and operator families.  pg_dump's sort then depended on object OID,
yielding spurious schema diffs.  After this change, OIDs affect dump
order only in the event of catalog corruption.  While pg_dump also
wrongly ignored pg_collation.collencoding, CREATE COLLATION restrictions
have been keeping that imperceptible in practical use.

Use techniques like we use for object types already having full sort key
coverage.  Where the pertinent queries weren't fetching the ignored sort
keys, this adds columns to those queries and stores those keys in memory
for the long term.

The ignorance of sort keys became more problematic when commit
172259afb5 added a schema diff test
sensitive to it.  Buildfarm member hippopotamus witnessed that.
However, dump order stability isn't a new goal, and this might avoid
other dump comparison failures.  Hence, back-patch to v13 (all supported
versions).

Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/20250707192654.9e.nmisch@google.com
Backpatch-through: 13

src/bin/pg_dump/common.c

@@ -17,6 +17,7 @@
 
 #include <ctype.h>
 
+#include "catalog/pg_am_d.h"
 #include "catalog/pg_class_d.h"
 #include "fe_utils/string_utils.h"
 #include "pg_backup_archiver.h"
@@ -49,6 +50,7 @@ static DumpableObject **tblinfoindex;
 static DumpableObject **typinfoindex;
 static DumpableObject **funinfoindex;
 static DumpableObject **oprinfoindex;
+static DumpableObject **aminfoindex;
 static DumpableObject **collinfoindex;
 static DumpableObject **nspinfoindex;
 static DumpableObject **extinfoindex;
@@ -57,6 +59,7 @@ static int	numTables;
 static int	numTypes;
 static int	numFuncs;
 static int	numOperators;
+static int	numAccessMethods;
 static int	numCollations;
 static int	numNamespaces;
 static int	numExtensions;
@@ -92,6 +95,7 @@ getSchemaData(Archive *fout, int *numTablesPtr)
 	TypeInfo   *typinfo;
 	FuncInfo   *funinfo;
 	OprInfo    *oprinfo;
+	AccessMethodInfo *aminfo;
 	CollInfo   *collinfo;
 	NamespaceInfo *nspinfo;
 	ExtensionInfo *extinfo;
@@ -103,7 +107,6 @@ getSchemaData(Archive *fout, int *numTablesPtr)
 	int			numProcLangs;
 	int			numCasts;
 	int			numTransforms;
-	int			numAccessMethods;
 	int			numOpclasses;
 	int			numOpfamilies;
 	int			numConversions;
@@ -166,7 +169,8 @@ getSchemaData(Archive *fout, int *numTablesPtr)
 	oprinfoindex = buildIndexArray(oprinfo, numOperators, sizeof(OprInfo));
 
 	pg_log_info("reading user-defined access methods");
-	getAccessMethods(fout, &numAccessMethods);
+	aminfo = getAccessMethods(fout, &numAccessMethods);
+	aminfoindex = buildIndexArray(aminfo, numAccessMethods, sizeof(AccessMethodInfo));
 
 	pg_log_info("reading user-defined operator classes");
 	getOpclasses(fout, &numOpclasses);
@@ -890,6 +894,17 @@ findOprByOid(Oid oid)
 	return (OprInfo *) findObjectByOid(oid, oprinfoindex, numOperators);
 }
 
+/*
+ * findAccessMethodByOid
+ *	  finds the DumpableObject for the access method with the given oid
+ *	  returns NULL if not found
+ */
+AccessMethodInfo *
+findAccessMethodByOid(Oid oid)
+{
+	return (AccessMethodInfo *) findObjectByOid(oid, aminfoindex, numAccessMethods);
+}
+
 /*
  * findCollationByOid
  *	  finds the entry (in collinfo) of the collation with the given oid

src/bin/pg_dump/pg_dump.c

@@ -1767,6 +1767,13 @@ selectDumpableProcLang(ProcLangInfo *plang, Archive *fout)
 static void
 selectDumpableAccessMethod(AccessMethodInfo *method, Archive *fout)
 {
+	/* see getAccessMethods() comment about v9.6. */
+	if (fout->remoteVersion < 90600)
+	{
+		method->dobj.dump = DUMP_COMPONENT_NONE;
+		return;
+	}
+
 	if (checkExtensionMembership(&method->dobj, fout))
 		return;					/* extension membership overrides all else */
 
@@ -5325,6 +5332,8 @@ getOperators(Archive *fout, int *numOprs)
 	int			i_oprnamespace;
 	int			i_rolname;
 	int			i_oprkind;
+	int			i_oprleft;
+	int			i_oprright;
 	int			i_oprcode;
 
 	/*
@@ -5336,6 +5345,8 @@ getOperators(Archive *fout, int *numOprs)
 					  "oprnamespace, "
 					  "(%s oprowner) AS rolname, "
 					  "oprkind, "
+					  "oprleft, "
+					  "oprright, "
 					  "oprcode::oid AS oprcode "
 					  "FROM pg_operator",
 					  username_subquery);
@@ -5353,6 +5364,8 @@ getOperators(Archive *fout, int *numOprs)
 	i_oprnamespace = PQfnumber(res, "oprnamespace");
 	i_rolname = PQfnumber(res, "rolname");
 	i_oprkind = PQfnumber(res, "oprkind");
+	i_oprleft = PQfnumber(res, "oprleft");
+	i_oprright = PQfnumber(res, "oprright");
 	i_oprcode = PQfnumber(res, "oprcode");
 
 	for (i = 0; i < ntups; i++)
@@ -5367,6 +5380,8 @@ getOperators(Archive *fout, int *numOprs)
 						  atooid(PQgetvalue(res, i, i_oprnamespace)));
 		oprinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
 		oprinfo[i].oprkind = (PQgetvalue(res, i, i_oprkind))[0];
+		oprinfo[i].oprleft = atooid(PQgetvalue(res, i, i_oprleft));
+		oprinfo[i].oprright = atooid(PQgetvalue(res, i, i_oprright));
 		oprinfo[i].oprcode = atooid(PQgetvalue(res, i, i_oprcode));
 
 		/* Decide whether we want to dump it */
@@ -5407,6 +5422,7 @@ getCollations(Archive *fout, int *numCollations)
 	int			i_collname;
 	int			i_collnamespace;
 	int			i_rolname;
+	int			i_collencoding;
 
 	/* Collations didn't exist pre-9.1 */
 	if (fout->remoteVersion < 90100)
@@ -5424,7 +5440,8 @@ getCollations(Archive *fout, int *numCollations)
 
 	appendPQExpBuffer(query, "SELECT tableoid, oid, collname, "
 					  "collnamespace, "
-					  "(%s collowner) AS rolname "
+					  "(%s collowner) AS rolname, "
+					  "collencoding "
 					  "FROM pg_collation",
 					  username_subquery);
 
@@ -5440,6 +5457,7 @@ getCollations(Archive *fout, int *numCollations)
 	i_collname = PQfnumber(res, "collname");
 	i_collnamespace = PQfnumber(res, "collnamespace");
 	i_rolname = PQfnumber(res, "rolname");
+	i_collencoding = PQfnumber(res, "collencoding");
 
 	for (i = 0; i < ntups; i++)
 	{
@@ -5452,6 +5470,7 @@ getCollations(Archive *fout, int *numCollations)
 			findNamespace(fout,
 						  atooid(PQgetvalue(res, i, i_collnamespace)));
 		collinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
+		collinfo[i].collencoding = atoi(PQgetvalue(res, i, i_collencoding));
 
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(collinfo[i].dobj), fout);
@@ -5561,19 +5580,28 @@ getAccessMethods(Archive *fout, int *numAccessMethods)
 	int			i_amhandler;
 	int			i_amtype;
 
-	/* Before 9.6, there are no user-defined access methods */
-	if (fout->remoteVersion < 90600)
-	{
-		*numAccessMethods = 0;
-		return NULL;
-	}
-
 	query = createPQExpBuffer();
 
-	/* Select all access methods from pg_am table */
-	appendPQExpBufferStr(query, "SELECT tableoid, oid, amname, amtype, "
-						 "amhandler::pg_catalog.regproc AS amhandler "
-						 "FROM pg_am");
+	/*
+	 * Select all access methods from pg_am table.  v9.6 introduced CREATE
+	 * ACCESS METHOD, so earlier versions usually have only built-in access
+	 * methods.  v9.6 also changed the access method API, replacing dozens of
+	 * pg_am columns with amhandler.  Even if a user created an access method
+	 * by "INSERT INTO pg_am", we have no way to translate pre-v9.6 pg_am
+	 * columns to a v9.6+ CREATE ACCESS METHOD.  Hence, before v9.6, read
+	 * pg_am just to facilitate findAccessMethodByOid() providing the
+	 * OID-to-name mapping.
+	 */
+	appendPQExpBufferStr(query, "SELECT tableoid, oid, amname, ");
+	if (fout->remoteVersion >= 90600)
+		appendPQExpBufferStr(query,
+							 "amtype, "
+							 "amhandler::pg_catalog.regproc AS amhandler ");
+	else
+		appendPQExpBufferStr(query,
+							 "'i'::pg_catalog.\"char\" AS amtype, "
+							 "'-'::pg_catalog.regproc AS amhandler ");
+	appendPQExpBufferStr(query, "FROM pg_am");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5631,6 +5659,7 @@ getOpclasses(Archive *fout, int *numOpclasses)
 	OpclassInfo *opcinfo;
 	int			i_tableoid;
 	int			i_oid;
+	int			i_opcmethod;
 	int			i_opcname;
 	int			i_opcnamespace;
 	int			i_rolname;
@@ -5640,11 +5669,20 @@ getOpclasses(Archive *fout, int *numOpclasses)
 	 * system-defined opclasses at dump-out time.
 	 */
 
-	appendPQExpBuffer(query, "SELECT tableoid, oid, opcname, "
-					  "opcnamespace, "
-					  "(%s opcowner) AS rolname "
-					  "FROM pg_opclass",
-					  username_subquery);
+	if (fout->remoteVersion >= 80300)
+		appendPQExpBuffer(query, "SELECT tableoid, oid, "
+						  "opcmethod, opcname, "
+						  "opcnamespace, "
+						  "(%s opcowner) AS rolname "
+						  "FROM pg_opclass",
+						  username_subquery);
+	else
+		appendPQExpBuffer(query, "SELECT tableoid, oid, "
+						  "opcamid AS opcmethod, opcname, "
+						  "opcnamespace, "
+						  "(%s opcowner) AS rolname "
+						  "FROM pg_opclass",
+						  username_subquery);
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -5655,6 +5693,7 @@ getOpclasses(Archive *fout, int *numOpclasses)
 
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
+	i_opcmethod = PQfnumber(res, "opcmethod");
 	i_opcname = PQfnumber(res, "opcname");
 	i_opcnamespace = PQfnumber(res, "opcnamespace");
 	i_rolname = PQfnumber(res, "rolname");
@@ -5669,6 +5708,7 @@ getOpclasses(Archive *fout, int *numOpclasses)
 		opcinfo[i].dobj.namespace =
 			findNamespace(fout,
 						  atooid(PQgetvalue(res, i, i_opcnamespace)));
+		opcinfo[i].opcmethod = atooid(PQgetvalue(res, i, i_opcmethod));
 		opcinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
 
 		/* Decide whether we want to dump it */
@@ -5706,6 +5746,7 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 	OpfamilyInfo *opfinfo;
 	int			i_tableoid;
 	int			i_oid;
+	int			i_opfmethod;
 	int			i_opfname;
 	int			i_opfnamespace;
 	int			i_rolname;
@@ -5724,7 +5765,7 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 	 * system-defined opfamilies at dump-out time.
 	 */
 
-	appendPQExpBuffer(query, "SELECT tableoid, oid, opfname, "
+	appendPQExpBuffer(query, "SELECT tableoid, oid, opfmethod, opfname, "
 					  "opfnamespace, "
 					  "(%s opfowner) AS rolname "
 					  "FROM pg_opfamily",
@@ -5740,6 +5781,7 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_opfname = PQfnumber(res, "opfname");
+	i_opfmethod = PQfnumber(res, "opfmethod");
 	i_opfnamespace = PQfnumber(res, "opfnamespace");
 	i_rolname = PQfnumber(res, "rolname");
 
@@ -5753,6 +5795,7 @@ getOpfamilies(Archive *fout, int *numOpfamilies)
 		opfinfo[i].dobj.namespace =
 			findNamespace(fout,
 						  atooid(PQgetvalue(res, i, i_opfnamespace)));
+		opfinfo[i].opfmethod = atooid(PQgetvalue(res, i, i_opfmethod));
 		opfinfo[i].rolname = pg_strdup(PQgetvalue(res, i, i_rolname));
 
 		/* Decide whether we want to dump it */

src/bin/pg_dump/pg_dump.h

@@ -219,6 +219,8 @@ typedef struct _oprInfo
 	DumpableObject dobj;
 	char	   *rolname;
 	char		oprkind;
+	Oid			oprleft;
+	Oid			oprright;
 	Oid			oprcode;
 } OprInfo;
 
@@ -232,12 +234,14 @@ typedef struct _accessMethodInfo
 typedef struct _opclassInfo
 {
 	DumpableObject dobj;
+	Oid			opcmethod;
 	char	   *rolname;
 } OpclassInfo;
 
 typedef struct _opfamilyInfo
 {
 	DumpableObject dobj;
+	Oid			opfmethod;
 	char	   *rolname;
 } OpfamilyInfo;
 
@@ -245,6 +249,7 @@ typedef struct _collInfo
 {
 	DumpableObject dobj;
 	char	   *rolname;
+	int			collencoding;
 } CollInfo;
 
 typedef struct _convInfo
@@ -662,6 +667,7 @@ extern TableInfo *findTableByOid(Oid oid);
 extern TypeInfo *findTypeByOid(Oid oid);
 extern FuncInfo *findFuncByOid(Oid oid);
 extern OprInfo *findOprByOid(Oid oid);
+extern AccessMethodInfo *findAccessMethodByOid(Oid oid);
 extern CollInfo *findCollationByOid(Oid oid);
 extern NamespaceInfo *findNamespaceByOid(Oid oid);
 extern ExtensionInfo *findExtensionByOid(Oid oid);

src/bin/pg_dump/pg_dump_sort.c

@@ -104,6 +104,8 @@ static DumpId postDataBoundId;
 
 
 static int	DOTypeNameCompare(const void *p1, const void *p2);
+static int	pgTypeNameCompare(Oid typid1, Oid typid2);
+static int	accessMethodNameCompare(Oid am1, Oid am2);
 static bool TopoSort(DumpableObject **objs,
 					 int numObjs,
 					 DumpableObject **ordering,
@@ -171,12 +173,39 @@ DOTypeNameCompare(const void *p1, const void *p2)
 	else if (obj2->namespace)
 		return 1;
 
-	/* Sort by name */
+	/*
+	 * Sort by name.  With a few exceptions, names here are single catalog
+	 * columns.  To get a fuller picture, grep pg_dump.c for "dobj.name = ".
+	 * Names here don't match "Name:" in plain format output, which is a
+	 * _tocEntry.tag.  For example, DumpableObject.name of a constraint is
+	 * pg_constraint.conname, but _tocEntry.tag of a constraint is relname and
+	 * conname joined with a space.
+	 */
 	cmpval = strcmp(obj1->name, obj2->name);
 	if (cmpval != 0)
 		return cmpval;
 
-	/* To have a stable sort order, break ties for some object types */
+	/*
+	 * Sort by type.  This helps types that share a type priority without
+	 * sharing a unique name constraint, e.g. opclass and opfamily.
+	 */
+	cmpval = obj1->objType - obj2->objType;
+	if (cmpval != 0)
+		return cmpval;
+
+	/*
+	 * To have a stable sort order, break ties for some object types.  Most
+	 * catalogs have a natural key, e.g. pg_proc_proname_args_nsp_index. Where
+	 * the above "namespace" and "name" comparisons don't cover all natural
+	 * key columns, compare the rest here.
+	 *
+	 * The natural key usually refers to other catalogs by surrogate keys.
+	 * Hence, this translates each of those references to the natural key of
+	 * the referenced catalog.  That may descend through multiple levels of
+	 * catalog references.  For example, to sort by pg_proc.proargtypes,
+	 * descend to each pg_type and then further to its pg_namespace, for an
+	 * overall sort by (nspname, typname).
+	 */
 	if (obj1->objType == DO_FUNC || obj1->objType == DO_AGG)
 	{
 		FuncInfo   *fobj1 = *(FuncInfo *const *) p1;
@@ -189,22 +218,10 @@ DOTypeNameCompare(const void *p1, const void *p2)
 			return cmpval;
 		for (i = 0; i < fobj1->nargs; i++)
 		{
-			TypeInfo   *argtype1 = findTypeByOid(fobj1->argtypes[i]);
-			TypeInfo   *argtype2 = findTypeByOid(fobj2->argtypes[i]);
-
-			if (argtype1 && argtype2)
-			{
-				if (argtype1->dobj.namespace && argtype2->dobj.namespace)
-				{
-					cmpval = strcmp(argtype1->dobj.namespace->dobj.name,
-									argtype2->dobj.namespace->dobj.name);
-					if (cmpval != 0)
-						return cmpval;
-				}
-				cmpval = strcmp(argtype1->dobj.name, argtype2->dobj.name);
-				if (cmpval != 0)
-					return cmpval;
-			}
+			cmpval = pgTypeNameCompare(fobj1->argtypes[i],
+									   fobj2->argtypes[i]);
+			if (cmpval != 0)
+				return cmpval;
 		}
 	}
 	else if (obj1->objType == DO_OPERATOR)
@@ -216,6 +233,57 @@ DOTypeNameCompare(const void *p1, const void *p2)
 		cmpval = (oobj2->oprkind - oobj1->oprkind);
 		if (cmpval != 0)
 			return cmpval;
+		/* Within an oprkind, sort by argument type names */
+		cmpval = pgTypeNameCompare(oobj1->oprleft, oobj2->oprleft);
+		if (cmpval != 0)
+			return cmpval;
+		cmpval = pgTypeNameCompare(oobj1->oprright, oobj2->oprright);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	else if (obj1->objType == DO_OPCLASS)
+	{
+		OpclassInfo *opcobj1 = *(OpclassInfo *const *) p1;
+		OpclassInfo *opcobj2 = *(OpclassInfo *const *) p2;
+
+		/* Sort by access method name, per pg_opclass_am_name_nsp_index */
+		cmpval = accessMethodNameCompare(opcobj1->opcmethod,
+										 opcobj2->opcmethod);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	else if (obj1->objType == DO_OPFAMILY)
+	{
+		OpfamilyInfo *opfobj1 = *(OpfamilyInfo *const *) p1;
+		OpfamilyInfo *opfobj2 = *(OpfamilyInfo *const *) p2;
+
+		/* Sort by access method name, per pg_opfamily_am_name_nsp_index */
+		cmpval = accessMethodNameCompare(opfobj1->opfmethod,
+										 opfobj2->opfmethod);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	else if (obj1->objType == DO_COLLATION)
+	{
+		CollInfo   *cobj1 = *(CollInfo *const *) p1;
+		CollInfo   *cobj2 = *(CollInfo *const *) p2;
+
+		/*
+		 * Sort by encoding, per pg_collation_name_enc_nsp_index. Technically,
+		 * this is not necessary, because wherever this changes dump order,
+		 * restoring the dump fails anyway.  CREATE COLLATION can't create a
+		 * tie for this to break, because it imposes restrictions to make
+		 * (nspname, collname) uniquely identify a collation within a given
+		 * DatabaseEncoding.  While pg_import_system_collations() can create a
+		 * tie, pg_dump+restore fails after
+		 * pg_import_system_collations('my_schema') does so. However, there's
+		 * little to gain by ignoring one natural key column on the basis of
+		 * those limitations elsewhere, so respect the full natural key like
+		 * we do for other object types.
+		 */
+		cmpval = cobj1->collencoding - cobj2->collencoding;
+		if (cmpval != 0)
+			return cmpval;
 	}
 	else if (obj1->objType == DO_ATTRDEF)
 	{
@@ -260,11 +328,132 @@ DOTypeNameCompare(const void *p1, const void *p2)
 		if (cmpval != 0)
 			return cmpval;
 	}
+	else if (obj1->objType == DO_CONSTRAINT)
+	{
+		ConstraintInfo *robj1 = *(ConstraintInfo *const *) p1;
+		ConstraintInfo *robj2 = *(ConstraintInfo *const *) p2;
+
+		/*
+		 * Sort domain constraints before table constraints, for consistency
+		 * with our decision to sort CREATE DOMAIN before CREATE TABLE.
+		 */
+		if (robj1->condomain)
+		{
+			if (robj2->condomain)
+			{
+				/* Sort by domain name (domain namespace was considered) */
+				cmpval = strcmp(robj1->condomain->dobj.name,
+								robj2->condomain->dobj.name);
+				if (cmpval != 0)
+					return cmpval;
+			}
+			else
+				return dbObjectTypePriority[DO_TYPE] - dbObjectTypePriority[DO_TABLE];
+		}
+		else if (robj2->condomain)
+			return dbObjectTypePriority[DO_TABLE] - dbObjectTypePriority[DO_TYPE];
+		else
+		{
+			/* Sort by table name (table namespace was considered already) */
+			cmpval = strcmp(robj1->contable->dobj.name,
+							robj2->contable->dobj.name);
+			if (cmpval != 0)
+				return cmpval;
+		}
+	}
+	else if (obj1->objType == DO_PUBLICATION_REL)
+	{
+		PublicationRelInfo *probj1 = *(PublicationRelInfo *const *) p1;
+		PublicationRelInfo *probj2 = *(PublicationRelInfo *const *) p2;
+
+		/* Sort by publication name, since (namespace, name) match the rel */
+		cmpval = strcmp(probj1->publication->dobj.name,
+						probj2->publication->dobj.name);
+		if (cmpval != 0)
+			return cmpval;
+	}
 
-	/* Usually shouldn't get here, but if we do, sort by OID */
+	/*
+	 * Shouldn't get here except after catalog corruption, but if we do, sort
+	 * by OID.  This may make logically-identical databases differ in the
+	 * order of objects in dump output.  Users will get spurious schema diffs.
+	 * Expect flaky failures of 002_pg_upgrade.pl test 'dump outputs from
+	 * original and restored regression databases match' if the regression
+	 * database contains objects allowing that test to reach here.  That's a
+	 * consequence of the test using "pg_restore -j", which doesn't fully
+	 * constrain OID assignment order.
+	 */
+	Assert(false);
 	return oidcmp(obj1->catId.oid, obj2->catId.oid);
 }
 
+/* Compare two OID-identified pg_type values by nspname, then by typname. */
+static int
+pgTypeNameCompare(Oid typid1, Oid typid2)
+{
+	TypeInfo   *typobj1;
+	TypeInfo   *typobj2;
+	int			cmpval;
+
+	if (typid1 == typid2)
+		return 0;
+
+	typobj1 = findTypeByOid(typid1);
+	typobj2 = findTypeByOid(typid2);
+
+	if (!typobj1 || !typobj2)
+	{
+		/*
+		 * getTypes() didn't find some OID.  Assume catalog corruption, e.g.
+		 * an oprright value without the corresponding OID in a pg_type row.
+		 * Report as "equal", so the caller uses the next available basis for
+		 * comparison, e.g. the next function argument.
+		 *
+		 * Unary operators have InvalidOid in oprleft (if oprkind='r') or in
+		 * oprright (if oprkind='l').  Caller already sorted by oprkind,
+		 * calling us only for like-kind operators.  Hence, "typid1 == typid2"
+		 * took care of InvalidOid.  (v14 removed postfix operator support.
+		 * Hence, when dumping from v14+, only oprleft can be InvalidOid.)
+		 */
+		Assert(false);
+		return 0;
+	}
+
+	if (!typobj1->dobj.namespace || !typobj2->dobj.namespace)
+		Assert(false);			/* catalog corruption */
+	else
+	{
+		cmpval = strcmp(typobj1->dobj.namespace->dobj.name,
+						typobj2->dobj.namespace->dobj.name);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	return strcmp(typobj1->dobj.name, typobj2->dobj.name);
+}
+
+/* Compare two OID-identified pg_am values by amname. */
+static int
+accessMethodNameCompare(Oid am1, Oid am2)
+{
+	AccessMethodInfo *amobj1;
+	AccessMethodInfo *amobj2;
+
+	if (am1 == am2)
+		return 0;
+
+	amobj1 = findAccessMethodByOid(am1);
+	amobj2 = findAccessMethodByOid(am2);
+
+	if (!amobj1 || !amobj2)
+	{
+		/* catalog corruption: handle like pgTypeNameCompare() does */
+		Assert(false);
+		return 0;
+	}
+
+	return strcmp(amobj1->dobj.name, amobj2->dobj.name);
+}
+
 
 /*
  * Sort the given objects into a safe dump order using dependency

src/test/regress/expected/publication.out

@@ -344,3 +344,11 @@ NOTICE:  drop cascades to table pub_test.testpub_nopk
 RESET SESSION AUTHORIZATION;
 DROP ROLE regress_publication_user, regress_publication_user2;
 DROP ROLE regress_publication_user_dummy;
+-- stage objects for pg_dump tests
+CREATE SCHEMA pubme CREATE TABLE t0 (c int, d int) CREATE TABLE t1 (c int);
+SET client_min_messages = 'ERROR';
+CREATE PUBLICATION dump_pub_1ct FOR TABLE ONLY pubme.t0;
+CREATE PUBLICATION dump_pub_2ct FOR TABLE ONLY pubme.t0, pubme.t1;
+CREATE PUBLICATION dump_pub_all FOR TABLE ONLY pubme.t0, pubme.t1
+  WITH (publish_via_partition_root = true);
+RESET client_min_messages;

src/test/regress/sql/publication.sql

@@ -218,3 +218,12 @@ DROP SCHEMA pub_test CASCADE;
 RESET SESSION AUTHORIZATION;
 DROP ROLE regress_publication_user, regress_publication_user2;
 DROP ROLE regress_publication_user_dummy;
+
+-- stage objects for pg_dump tests
+CREATE SCHEMA pubme CREATE TABLE t0 (c int, d int) CREATE TABLE t1 (c int);
+SET client_min_messages = 'ERROR';
+CREATE PUBLICATION dump_pub_1ct FOR TABLE ONLY pubme.t0;
+CREATE PUBLICATION dump_pub_2ct FOR TABLE ONLY pubme.t0, pubme.t1;
+CREATE PUBLICATION dump_pub_all FOR TABLE ONLY pubme.t0, pubme.t1
+  WITH (publish_via_partition_root = true);
+RESET client_min_messages;