source: npl/mailserver/dspam/dspam-3.10.2/doc/sqlite_drv.txt

$Id: sqlite_drv.txt,v 1.3 2011/07/08 23:01:42 pcockings Exp $

COPYRIGHT (C) 2002-2012 DSPAM Project
http://dspam.sourceforge.net

LICENSE

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.

ABOUT

- - ----------------------------------------------------------------------- - -
- - Note: The sqlite_drv for using SQLite2 (>2.7.7) is not widely used and  - -
- -       is likely to be removed in a future release. Please consider      - -
- -       moving to SQLite3 and the sqlite3_drv instead.                    - -
- - ----------------------------------------------------------------------- - -

sqlite_drv and sqlite3_drv are SQLite storage drivers for DSPAM v3.0 and above.
These drivers enables DSPAM to read and write all token, signature, and
statistics data from individual SQLite databases created for each user.

WARNING: SQLite is not designed to function over NFS. If your system is large
         enough to require NFS, it is strongly recommended you use a stateful
         SQL driver, such as MySQL or PostgreSQL.

1. CONFIGURING DSPAM

To configure DSPAM to use a driver, use the following arguments while running
DSPAM's configure:

--with-storage-driver=sqlite_drv
Tells DSPAM to use the sqlite_drv driver

--with-storage-driver=sqlite3_drv
Tells DSPAM to use the sqlite3_drv driver (for SQLite v3.x)

--with-sqlite-libraries=/path/to/libs
Tells DSPAM where to find the SQLite library (libsqlite.so).

--with-sqlite-includes=/path/to/includes
Tells DSPAM where to find the SQLite headers.

After configure has successfully finished, build and install DSPAM using the
instructions from DSPAM's readme.

2. OBJECT CREATION

The drivers will automatically create the necessary database objects for each
user upon first use of DSPAM by that user.

3. PURGING

The purge script should be run against all databases periodically. The best
way to do this is to use a find recipe such as:

find /usr/local/var/dspam/data -name "*.sdb" -exec sqlite {} < /var/dspam/purge-2.sql \;

or use sqlite3 and purge-3.sql if you're running sqlite3_drv.

You may also wish to occasionally compact your databases. This should only
be run once in a great while, and is not entirely necessary as SQLite will
automatically reclaim space the next time it is used.  Nevertheless, some
databases can grow quite large if not purged well enough. Another find
recipe such as the one below can be used to compact all databases on a
system.

find /usr/local/var/dspam/data -name "*.sdb" -exec echo 'vacuum;' \| sqlite {} \;

or sqlite3, if you're running sqlite3_drv.

4. TUNING

There are some tuning parameters which can be set, discussed here:
http://sqlite.org/pragma.html#syntax

Whenever sqlite_drv connects to a database, it will read
$DSPAM_HOME/sqlite.pragma and execute any commands found in the file. For
example, if you wish to turn off synchronous mode (which speeds up queries by
as much as 50x, but could potentially risk database corruption on system
crash), you could add this line to sqlite.pragma:

PRAGMA synchronous = OFF

Note: - Do not put a semicolon at the end of any statements in sqlite.pragma.
      - Comments are not allowed in sqlite.pragma. Anything you add to the file
        will be executed without being filtered.

ERRORS

Any SQL errors will be reported to LOGDIR/sql.errors as well as the standard
syslog facilities (although the query will be truncated).

QUESTIONS

Please contact the dspam-dev mailing list with any questions or constructive
feedback.

Initial storage driver written by Jonathan A. Zdziarski <jonathan@nuclearelephant.com>
and later enhanced by Stevan Bajic <stevan@bajic.ch> for DSPAM 3.9.0.