.. _limits:

Limits
------

Locmem
......

Locmem is a just a dict stored in a single Python process.
It’s not shared between processes, so don’t use locmem with django-cachalot
in a multi-processes project, if you use RQ or Celery for instance.

.. _Raw queries limits:

Raw SQL queries
...............

.. note::
   Don’t worry if you don’t understand what follow. That probably means you
   don’t use raw queries, and therefore are not directly concerned by
   those potential issues.

By default, django-cachalot tries to invalidate its cache after a raw query.
It detects if the raw query contains ``UPDATE``, ``INSERT`` or ``DELETE``,
and then invalidates the tables contained in that query by comparing
with models registered by Django.

This is quite robust, so if a query is not invalidated automatically
by this system, please :ref:`send a bug report <reporting>`.
In the meantime, you can use :ref:`the API <API>` to manually invalidate
the tables where data has changed.

However, this simple system can be too efficient in some cases and lead to
unwanted extra invalidations.
In such cases, you may want to partially disable this behaviour by
:ref:`dynamically overriding settings <Dynamic overriding>` to set
:ref:`CACHALOT_INVALIDATE_RAW` to ``False``.
After that, use :ref:`the API <API>` to manually invalidate the tables
you modified.