also check if it's a system catalog

Author: jeewonhh

src/catalog/catalog.cpp

@@ -954,13 +954,14 @@ optional_ptr<SchemaCatalogEntry> Catalog::GetSchema(CatalogEntryRetriever &retri
 	auto entries = GetCatalogEntries(retriever, catalog_name, schema_name);
 	auto &context = retriever.GetContext();
 	for (idx_t i = 0; i < entries.size(); i++) {
-		if (!context.db->GetDatabaseManager().GetDatabase(context, entries[i].catalog)) {
-			// check if the catalog is attached before we try to get the catalog
+		auto entry_name = IsInvalidCatalog(entries[i].catalog) ? GetDefaultCatalog(retriever) : entries[i].catalog;
+		// check whether the catalog is attached before trying to get it
+		if (!context.db->GetDatabaseManager().GetDatabase(context, entry_name)) {
 			continue;
 		}
 		auto on_not_found = i + 1 == entries.size() ? if_not_found : OnEntryNotFound::RETURN_NULL;
 		auto &catalog = Catalog::GetCatalog(retriever, entries[i].catalog);
-		auto result = catalog.GetSchema(retriever.GetContext(), schema_name, on_not_found, error_context);
+		auto result = catalog.GetSchema(context, schema_name, on_not_found, error_context);
 		if (result) {
 			return result;
 		}

src/catalog/catalog_search_path.cpp

@@ -221,17 +221,17 @@ string CatalogSearchPath::GetDefaultCatalog(const string &schema) {
 }
 
 vector<string> CatalogSearchPath::GetCatalogsForSchema(const string &schema) {
-	vector<string> schemas;
+	vector<string> catalogs;
 	if (DefaultSchemaGenerator::IsDefaultSchema(schema)) {
-		schemas.push_back(SYSTEM_CATALOG);
+		catalogs.push_back(SYSTEM_CATALOG);
 	} else {
 		for (auto &path : paths) {
 			if (StringUtil::CIEquals(path.schema, schema)) {
-				schemas.push_back(path.catalog);
+				catalogs.push_back(path.catalog);
 			}
 		}
 	}
-	return schemas;
+	return catalogs;
 }
 
 vector<string> CatalogSearchPath::GetSchemasForCatalog(const string &catalog) {

src/main/database_manager.cpp

@@ -32,6 +32,9 @@ optional_ptr<AttachedDatabase> DatabaseManager::GetDatabase(ClientContext &conte
 	if (StringUtil::Lower(name) == TEMP_CATALOG) {
 		return context.client_data->temporary_objects.get();
 	}
+	if (StringUtil::Lower(name) == SYSTEM_CATALOG) {
+		return system;
+	}
 	return reinterpret_cast<AttachedDatabase *>(databases->GetEntry(context, name).get());
 }