Use r13844 workaround for SQLServer only.

git-svn-id: http://svn.redmine.org/redmine/trunk@13845 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine/nested_set/issue_nested_set.rb

@@ -149,12 +149,17 @@ module Redmine
       end
 
       def lock_nested_set
-        lock = true
         if self.class.connection.adapter_name =~ /sqlserver/i
           lock = "WITH (ROWLOCK HOLDLOCK UPDLOCK)"
-        end
+          # Custom lock for SQLServer
+          # This can be problematic if root_id or parent root_id changes
+          # before locking
           sets_to_lock = [root_id, parent.try(:root_id)].compact.uniq
           self.class.reorder(:id).where(:root_id => sets_to_lock).lock(lock).ids
+        else
+          sets_to_lock = [id, parent_id].compact
+          self.class.reorder(:id).where("root_id IN (SELECT root_id FROM #{self.class.table_name} WHERE id IN (?))", sets_to_lock).lock.ids
+        end
       end
 
       def nested_set_scope