Since we are on the topic of what prompted us to use PostgreSQL, I figured I would share my experiences as well, and some additional thoughts that I had.
I chose PostgreSQL about 2 years ago when I realized that the application I was building needed something more robust than MySQL. I found the learning curve to be a bit steep at first, but eventually got the hang of it and have developed a real appreciation for PostgreSQL. Unlike many members here I won't say I would never go back to MySQL, because there are some circumstances where I would (where I need an RDBMS-like interface but not an RDBMS, f. ex. MySQL's heap tables could be very useful for real-time control systems). However, I am actually seeing less and less value in MySQL as I become more familiar with the extensibility features in PostgreSQL.
Anyway one additional thought I had was that it should be possible to write parsers for text files in PL/PERLu and then plug those in as views. In this way, files such as /etc/passwd or even /var/log/messages could be used as if they were tables in the database. Information from these tables could then be selected into other tables, presented directly to an application, etc. While it mught be possible to do the same for MySQL, it would be much more work. Imagine being able to run a query such as:
select * from logs.iptables where proto = 'TCP' and td_entered > '2003-01-01' and port = (select port from sysinfo.services where service='ssh');
in order to get every hit against the ssh service on the firewall in the current year. Of course, I imagine, it would take some time to run ;-) But for generating reports of system activirt, I would not assume this to be a problem.
Next question-- any ideas how one could generate something like MySQL's heap tables (maybe in shared memory?) within PostgreSQL?
