Subject Re: [firebird-support] Re: a few How To......s
Author Svein Erling Tysvaer
yogiyang007 wrote:
> Hi,
> This means I will have to mess with SystemTable for this. That is a
> bit frightning for me as I am a beginner in FB.

In Firebird, readers don't block writers, and I wouldn't consider
selecting from system tables as messing with them. Inserting into,
updating or deleting from them is another matter (I haven't tried, but I
would also recommend avoiding 'select ... from rdb$... with lock').

What can (or maybe could) cause trouble, is mixing DDL and DML. E.g. try
avoid changing or deleting a field definition whilst someone has a yet
uncommitted change to that field. I'm not certain whether that example
could actually cause problems, but we have occasionally had trouble when
modifying a database while in production (I don't know whether we've
had any corruption, but at least we had to restart Firebird for such a
reason a year or two ago).

The FAQ on contains some
useful system queries.