Hi,

> I'd like to hear from you some thoughts (pros. and cons.) on using EXTERNAL
> tables for database logging (I'm planning to have triggers to LOG user
> activity on insert/update/delete of records).

from my own audit/trail experience ;-), don't use them.

External tables do have some restrictions you should be aware of:

- Only INSERT and SELECT is supported
- No BLOB and array support
- DML operations are outside transaction control
...

You'd better keep the logs inside the database and pump them
regularly to another database by using the two-phase-commit
protocol.

Regards,
Thomas Steinmaurer
IB LogManager 2.1 - The Logging/Auditing Tool for InterBase and Firebird
http://www.iblogmanager.com