diff --git a/lib/redmine_dmsf/webdav/dmsf_resource.rb b/lib/redmine_dmsf/webdav/dmsf_resource.rb
index 66ff3f6f..1fb236b8 100644
--- a/lib/redmine_dmsf/webdav/dmsf_resource.rb
+++ b/lib/redmine_dmsf/webdav/dmsf_resource.rb
@@ -49,10 +49,10 @@ module RedmineDmsf
         unless @childern
           @children = []
           if collection?
-            folder.subfolders.visible.map do |p|
+            folder.subfolders.select(:title).visible.map do |p|
               @children.push child(p.title)
             end
-            folder.files.visible.map do |p|
+            folder.files.select(:name).visible.map do |p|
               @children.push child(p.name)
             end
           end
diff --git a/lib/redmine_dmsf/webdav/index_resource.rb b/lib/redmine_dmsf/webdav/index_resource.rb
index bc622ef3..bc39e8b4 100644
--- a/lib/redmine_dmsf/webdav/index_resource.rb
+++ b/lib/redmine_dmsf/webdav/index_resource.rb
@@ -26,7 +26,8 @@ module RedmineDmsf
       def children
         unless @projects
           @projects = []
-          Project.has_module(:dmsf).where(Project.allowed_to_condition(
+          Project.select(:identifier).has_module(:dmsf).where(
+            Project.allowed_to_condition(
               User.current, :view_dmsf_folders)).order('lft').all.each do |p|
             @projects << child(p.identifier)
           end
diff --git a/lib/redmine_dmsf/webdav/project_resource.rb b/lib/redmine_dmsf/webdav/project_resource.rb
index 73d19be4..459f0d96 100644
--- a/lib/redmine_dmsf/webdav/project_resource.rb
+++ b/lib/redmine_dmsf/webdav/project_resource.rb
@@ -27,10 +27,10 @@ module RedmineDmsf
         unless @children          
           @children = []
           if project
-            project.dmsf_folders.visible.map do |p|
+            project.dmsf_folders.select(:title).visible.map do |p|
               @children.push child(p.title)
             end
-            project.dmsf_files.visible.map do |p|
+            project.dmsf_files.select(:name).visible.map do |p|
               @children.push child(p.name)              
             end
           end