diff --git a/src/import_pipeline.cc b/src/import_pipeline.cc
index 680f3d67..f4cd7d5f 100644
--- a/src/import_pipeline.cc
+++ b/src/import_pipeline.cc
@@ -71,10 +71,12 @@ bool Indexer_Parse(DiagnosticsEngine* diag_engine,
   auto& request = *opt_request;
   ICacheManager cache;
 
-  // dummy one to trigger refresh semantic highlight
+  // Dummy one to trigger refresh semantic highlight.
   if (request.path.empty()) {
+    IndexUpdate dummy;
+    dummy.refresh = true;
     queue->on_indexed.PushBack(
-        Index_OnIndexed(IndexUpdate{}, PerformanceImportFile()), false);
+        Index_OnIndexed(std::move(dummy), PerformanceImportFile()), false);
     return false;
   }
 
@@ -224,12 +226,14 @@ void QueryDb_OnIndexed(QueueManager* queue,
                        WorkingFiles* working_files,
                        Index_OnIndexed* response) {
 
-  if (response->update.file_id < 0) { // dummy
+  if (response->update.refresh) {
     LOG_S(INFO) << "Loaded project. Refresh semantic highlight for all working file.";
     std::lock_guard<std::mutex> lock(working_files->files_mutex);
     for (auto& f : working_files->files) {
-      int file_id = db->name2file_id[LowerPathIfInsensitive(f->filename)];
-      QueryFile* file = &db->files[file_id];
+      std::string filename = LowerPathIfInsensitive(f->filename);
+      if (db->name2file_id.find(filename) == db->name2file_id.end())
+        continue;
+      QueryFile* file = &db->files[db->name2file_id[filename]];
       EmitSemanticHighlighting(db, semantic_cache, f.get(), file);
     }
     return;
diff --git a/src/include_complete.cc b/src/include_complete.cc
index 056a5b2b..ea33fa33 100644
--- a/src/include_complete.cc
+++ b/src/include_complete.cc
@@ -106,8 +106,6 @@ void IncludeComplete::Rescan() {
     SetThreadName("scan_includes");
     Timer timer;
 
-    // InsertIncludesFromDirectory(g_config->projectRoot,
-    //                             false /*use_angle_brackets*/);
     for (const std::string& dir : project_->quote_include_directories)
       InsertIncludesFromDirectory(dir, false /*use_angle_brackets*/);
     for (const std::string& dir : project_->angle_include_directories)
diff --git a/src/project.cc b/src/project.cc
index 545f8cf8..df568423 100644
--- a/src/project.cc
+++ b/src/project.cc
@@ -563,8 +563,8 @@ void Project::Index(QueueManager* queue,
     queue->index_request.PushBack(Index_Request(entry.filename, entry.args,
                                                 is_interactive, *content, id));
   });
-  // dummy request to indicate that project is loaded and
-  // trigger refreshing semantic highlight for all working files
+  // Dummy request to indicate that project is loaded and
+  // trigger refreshing semantic highlight for all working files.
   queue->index_request.PushBack(Index_Request("", {}, false, ""));
 }
 
diff --git a/src/query.h b/src/query.h
index a146df9f..571f1a4e 100644
--- a/src/query.h
+++ b/src/query.h
@@ -99,7 +99,10 @@ struct IndexUpdate {
   static IndexUpdate CreateDelta(IndexFile* previous,
                                  IndexFile* current);
 
-  int file_id = -1;
+  int file_id;
+
+  // Dummy one to refresh all semantic highlight.
+  bool refresh = false;
 
   // File updates.
   std::optional<std::string> files_removed;