EricFries

♥ git checkout -b experimental-theories
Switched to a new branch 'experimental-theories'

EricFries

Django Performance Guidelines

ORM

• Incorrect usage of the Django ORM is a common cause of performance issues. Therefore, it is important to know when querysets are evaluated (i.e., hit the database)
  • Common mistakes that cause the queryset to be evaulated include iterating over the queryset or calling any of len(), list(), bool() with the queryset as an argument.
  • Reference: (QuerySet API reference | Django documentation | Django)
• Use exists() to check if a queryset has any results in it.
  • Good:

   queryset = Account.objects.filter(some_attribute=True)