Revert "Merge branch 'optimize-self-and-descendants' into 'master'"

This reverts merge request !59599

app/models/namespaces/traversal/linear.rb

@@ -86,7 +86,25 @@ module Namespaces
         raise UnboundedSearch.new('Must bound search by a top') unless top
 
         without_sti_condition
-          .traversal_ids_contains("{#{top.id}}")
+          .traversal_ids_contains(latest_traversal_ids(top))
+      end
+
+      # traversal_ids are a cached value.
+      #
+      # The traversal_ids value in a loaded object can become stale when compared
+      # to the database value. For example, if you load a hierarchy and then move
+      # a group, any previously loaded descendant objects will have out of date
+      # traversal_ids.
+      #
+      # To solve this problem, we never depend on the object's traversal_ids
+      # value. We always query the database first with a sub-select for the
+      # latest traversal_ids.
+      #
+      # Note that ActiveRecord will cache query results. You can avoid this by
+      # using `Model.uncached { ... }`
+      def latest_traversal_ids(namespace = self)
+        without_sti_condition.where('id = (?)', namespace)
+                .select('traversal_ids as latest_traversal_ids')
       end
     end
   end