====================================== PostgreSQL specific database functions ====================================== All of these functions are available from the ``django.contrib.postgres.functions`` module. .. currentmodule:: django.contrib.postgres.functions ``TransactionNow`` ================== .. class:: TransactionNow() Returns the date and time on the database server that the current transaction started. If you are not in a transaction it will return the date and time of the current statement. This is a complement to :class:`django.db.models.functions.Now`, which returns the date and time of the current statement. Note that only the outermost call to :func:`~django.db.transaction.atomic()` sets up a transaction and thus sets the time that ``TransactionNow()`` will return; nested calls create savepoints which do not affect the transaction time. Usage example:: >>> from django.contrib.postgres.functions import TransactionNow >>> Article.objects.filter(published__lte=TransactionNow()) ]>