添加为空判断

app/models/query.rb

@@ -492,6 +492,7 @@ class Query < ActiveRecord::Base
 
   def project_statement
     project_clauses = []
+    unless project.descendants.blank?
       if project && !project.descendants.active.empty?
         ids = [project.id]
         if has_filter?("subproject_id")
@@ -512,6 +513,7 @@ class Query < ActiveRecord::Base
       elsif project
         project_clauses << "#{Project.table_name}.id = %d" % project.id
       end
+    end
     project_clauses.any? ? project_clauses.join(' AND ') : nil
   end