PostgreSQL specific database functionsLink para este cabeçalho

All of these functions are available from the django.contrib.postgres.functions module.

RandomUUIDLink para este cabeçalho

class RandomUUIDLink para esta definição

Returns a version 4 UUID.

Requires PostgreSQL 9.4 or greater.

The pgcrypto extension must be installed. You can use the CryptoExtension migration operation to install it.

Usage example:

Code
>>> from django.contrib.postgres.functions import RandomUUID
>>> Article.objects.update(uuid=RandomUUID())

TransactionNowLink para este cabeçalho

class TransactionNowLink para esta definição

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 django.db.models.functions.Now, which returns the date and time of the current statement.

Note that only the outermost call to 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:

Code
>>> from django.contrib.postgres.functions import TransactionNow
>>> Article.objects.filter(published__lte=TransactionNow())
<QuerySet [<Article: How to Django>]>