It is not possible to create or use temp tables or cte's inside (instead of) triggers. Yet I need a storage for intermediate results, generated within the trigger. So I created a normal table to be used as a 'tempstore' for these kind of data. At the end of the trigger the generated data are deleted from the table, leaving it empty for the next use. For as I can see now there will be only one connection that writes. Is this sound/safe, is there an other/better way?