Add fastpaths for when no objects are found

danielgustafsson · danielgustafsson · commit 9c733951049b · 2024-10-02T13:08:55.000+02:00
If there are no objects found, there is no reason to inspect the result columns and mallocing a zero-sized (which will be 1 byte in reality) heap buffer for it. Add a fast-path for immediately returning like how other object inspection functions are already doing it. Reviewed-by: Ranier Vilela <ranier.vf@gmail.com> Discussion: https://postgr.es/m/C2F05B3C-1414-45DD-AE09-6FEE4D0F89BD@yesql.se
diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
@@ -4314,6 +4314,9 @@ getPublications(Archive *fout)
 
 	ntups = PQntuples(res);
 
+	if (ntups == 0)
+		goto cleanup;
+
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_pubname = PQfnumber(res, "pubname");
@@ -4352,6 +4355,8 @@ getPublications(Archive *fout)
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(pubinfo[i].dobj), fout);
 	}
+
+cleanup:
 	PQclear(res);
 
 	destroyPQExpBuffer(query);
@@ -5817,7 +5822,7 @@ getExtensions(Archive *fout, int *numExtensions)
 	int			ntups;
 	int			i;
 	PQExpBuffer query;
-	ExtensionInfo *extinfo;
+	ExtensionInfo *extinfo = NULL;
 	int			i_tableoid;
 	int			i_oid;
 	int			i_extname;
@@ -5837,6 +5842,8 @@ getExtensions(Archive *fout, int *numExtensions)
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
 	ntups = PQntuples(res);
+	if (ntups == 0)
+		goto cleanup;
 
 	extinfo = (ExtensionInfo *) pg_malloc(ntups * sizeof(ExtensionInfo));
 
@@ -5866,6 +5873,7 @@ getExtensions(Archive *fout, int *numExtensions)
 		selectDumpableExtension(&(extinfo[i]), dopt);
 	}
 
+cleanup:
 	PQclear(res);
 	destroyPQExpBuffer(query);
 
