django-dbcleanup

Easily monitor database usage - and clean it up (based on your django models)

This pluggable app provides:

• visibility over database disk space usage for your models
• command to remove unused tables and recover disk space
• remove historical data from models that have any DateTimeField (configurable in the project settings.py)

Usage

model and admin view

dbcleanup.Table is an unmanaged model mapped to information tables in MySQL and PostgreSQL and added to django admin

command

dbcleanup is the management command that can be used (or scheduled) to remove unused

$ ./manage.py dbcleanup -h
usage: manage.py dbcleanup [-h] [-f] [-i] [-j {tables,history,analyze,migrations}] [--no-fk] [--version] [-v {0,1,2,3}] [--settings SETTINGS] [--pythonpath PYTHONPATH] [--traceback] [--no-color]
                           [--force-color] [--skip-checks]

Remove database tables that do not map to any models, such as when a django app is removed/disabled.

optional arguments:
  -h, --help            show this help message and exit
  -f, --force           Delete the items (instead of just listing them)
  -i, --interactive     Ask which items to delete, interactively
  -j {tables,history,analyze,migrations}, --just {tables,history,analyze,migrations}
                        Perform only a subset of actions
  --no-fk               Disable FOREIGNKEY_CHECK when DROPping tables - CAREFUL! use only if you are sure the constraints are not from a table in use (ie: circular dependencies between drop candidates)

Need to use --force or --interactive to actually perform changes, otherwise it'll be a dry run.
Covered actions are:

• tables: remove database tables that do not map to any model (ie: when a app is removed from the project, there is no migration to delete the tables) - use settings.DBCLEANUP_REQUIRED_TABLES to whitelist tables that would otherwise be removed
• history: remove old records for the models defined in settings.DBCLEANUP_HISTORY_MODELS (more below)
• analyze: only for MySQL - force analyze on all the tables to update the row count and size estimates
• migrations: remove migrations (from django_migrations table) that not in the project migration path (ie: after migration squashing and reset)

historical data

settings.DBCLEANUP_HISTORY_MODELS is a list of tuples where each tuple is (MODEL_NAME, DAYS_TO_KEEP, DATE_TIME_FIELD_NAME).

# someproject/settings.py
DBCLEANUP_HISTORY_MODELS = [
    ('notifications.notification', 365, 'time'),
    ...
]

With this setup, when ./manage.py dbcleanup -j history is executed, all notifications.Notification entries with time older than 365 days would be deleted.
History cleanup is skipped if it would cascade into other models (unless it's a multi-table model and it would cascade to the parent model).