Maintain DG3 must be done. How often depends on how many users and how active theiy are.

These routines are used for cleaning up the session in db.db.

First create a start command for running manage from command prompt. This example are for DG3v4 run on IIS and are named m.bat

@echo Start the DG3 manage command
SET DJANGO_SETTINGS_MODULE=web.settings
SET PYTHONPATH=C:\inetpub\DeployedDG3Apps4\MyAppName\web;C:\DEDS\;C:\DEDS\
"C:\DEDS\python.exe" "C:\inetpub\DeployedDG3Apps4\MyAppName\web\manage.py" %1 %2 %3 %4

Next do session cleanup using the m.bat just created

m clearsessions

Next run the dbshell and do vacuum

m dbshell
in shell run
VACUUM;

Then your db.db should be back on a reasonable size