Cache typarray for fast lookups in binary upgrade mode

When upgrading a large schema it adds significant overhead to perform
individual catalog lookups per relation in order to retrieve Oid for
preserving Oid calls. This instead adds the typarray to the TypeInfo
cache which then allows for fast lookups using the existing API. A
35% reduction of pg_dump runtime in binary upgrade mode was observed
with this change.

Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/8F1F1E1D-D17B-4B33-B014-EDBCD15F3F0B@yesql.se

src/bin/pg_dump/pg_dump.c

@@ -5412,23 +5412,15 @@ binary_upgrade_set_type_oids_by_type_oid(Archive *fout,
 	Oid			pg_type_array_oid;
 	Oid			pg_type_multirange_oid;
 	Oid			pg_type_multirange_array_oid;
+	TypeInfo   *tinfo;
 
 	appendPQExpBufferStr(upgrade_buffer, "\n-- For binary upgrade, must preserve pg_type oid\n");
 	appendPQExpBuffer(upgrade_buffer,
 					  "SELECT pg_catalog.binary_upgrade_set_next_pg_type_oid('%u'::pg_catalog.oid);\n\n",
 					  pg_type_oid);
 
-	appendPQExpBuffer(upgrade_query,
+	tinfo = findTypeByOid(pg_type_oid);
-					  "SELECT typarray "
+	pg_type_array_oid = tinfo->typarray;
-					  "FROM pg_catalog.pg_type "
-					  "WHERE oid = '%u'::pg_catalog.oid;",
-					  pg_type_oid);
-
-	res = ExecuteSqlQueryForSingleRow(fout, upgrade_query->data);
-
-	pg_type_array_oid = atooid(PQgetvalue(res, 0, PQfnumber(res, "typarray")));
-
-	PQclear(res);
 
 	if (!OidIsValid(pg_type_array_oid) && force_array_type)
 		pg_type_array_oid = get_next_possible_free_pg_type_oid(fout, upgrade_query);
@@ -5910,6 +5902,7 @@ getTypes(Archive *fout)
 	int			i_typtype;
 	int			i_typisdefined;
 	int			i_isarray;
+	int			i_typarray;
 
 	/*
 	 * we include even the built-in types because those may be used as array
@@ -5930,7 +5923,7 @@ getTypes(Archive *fout)
 						 "typnamespace, typacl, "
 						 "acldefault('T', typowner) AS acldefault, "
 						 "typowner, "
-						 "typelem, typrelid, "
+						 "typelem, typrelid, typarray, "
 						 "CASE WHEN typrelid = 0 THEN ' '::\"char\" "
 						 "ELSE (SELECT relkind FROM pg_class WHERE oid = typrelid) END AS typrelkind, "
 						 "typtype, typisdefined, "
@@ -5957,6 +5950,7 @@ getTypes(Archive *fout)
 	i_typtype = PQfnumber(res, "typtype");
 	i_typisdefined = PQfnumber(res, "typisdefined");
 	i_isarray = PQfnumber(res, "isarray");
+	i_typarray = PQfnumber(res, "typarray");
 
 	for (i = 0; i < ntups; i++)
 	{
@@ -5989,6 +5983,8 @@ getTypes(Archive *fout)
 		else
 			tyinfo[i].isArray = false;
 
+		tyinfo[i].typarray = atooid(PQgetvalue(res, i, i_typarray));
+
 		if (tyinfo[i].typtype == TYPTYPE_MULTIRANGE)
 			tyinfo[i].isMultirange = true;
 		else

src/bin/pg_dump/pg_dump.h

@@ -200,6 +200,7 @@ typedef struct _typeInfo
 	const char *rolname;
 	Oid			typelem;
 	Oid			typrelid;
+	Oid			typarray;
 	char		typrelkind;		/* 'r', 'v', 'c', etc */
 	char		typtype;		/* 'b', 'c', etc */
 	bool		isArray;		/* true if auto-generated array type */