add: more basic macro stuff

add: more efficient relay loading (only ids)

src/models/junction_relay_schedule.c

@@ -87,3 +87,14 @@ junction_relay_schedule_remove_for_relay(int relay_id)
 
     return rc == SQLITE_DONE;
 }
+
+int*
+junction_relay_schedule_get_relay_ids_with_schedule(int schedule_id)
+{
+    sqlite3_stmt *stmt;
+
+    sqlite3_prepare_v2(global_database, "SELECT relay_id FROM junction_relay_schedule WHERE schedule_id=?1;", -1, &stmt, NULL);
+    sqlite3_bind_int(stmt, 1, schedule_id);
+
+    return database_helper_get_ids(stmt);
+}