Using Databases for event logging

Hi All,

What is the correct method of connecting to an sqlite3 database?
Also, what is 'best practice' to secure against SQL injection?

I am trying to write event data, starting off with a very simple
configuration in my main exim.conf file:

LOGDB   = /var/log/mail/data.db
# LOGDB set because value used on more than one occasion: it makes
changing the configuration later simpler.
event_action    = ${lookup sqlite {file=LOGDB
         \
                  INSERT INTO exim_log (timestamp,host,msg) VALUES (
         \
                    '$tod_log'
         \
                  , '$host_address'
         \
                  , '(M) ${event_name}: ${event_data} '
         \
                );}}

This produces an entry in the panic.log
1uPMnA-000000006oD-1Iin failed to expand event_action msg:complete in
main: absolute file name expected for "sqlite" lookup

Ultimately (once testing is complete), I may transfer over to a
postgresql database. Would this change the answer/advice?
If helpful, Exim version 4.98.2

Many thanks,
Phil

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