Hello,

I'm not sure how to interpret the following result in the monitoring
tables regarding some transaction counters. I'm querying the monitoring
tables of a Firebird 2.1.2 database (Classic on Windows) with an
explicitely started client transaction (using IBO) set to read-only,
repeatable read, auto-commit = false.

With the following result.

* In MON$DATABASE

MON$OLDEST_TRANSACTION => 29117
MON$OLDEST_ACTIVE => 29710
MON$OLDEST_SNAPSHOT => 29710
MON$NEXT_TRANSACTION => 29710

* In MON$TRANSACTIONS

I see two records with the following MON$TRANSACTION_IDs:

29710
29698

Both marked with MON$STATE = 1


* Querying the header page gives the following result:

OIT: 29117
OAT: 29709
OST: 29709
NT: 29710


A few questions:

- Why isn't there a gap between MON$OLDEST_ACTIVE and
MON$NEXT_TRANSACTION? I would expect at least a gap of 1.
- Why do I see a record in MON$TRANSACTIONS with MON$TRANSACTION_ID =
29698 but not in any transaction counters either via MON$DATABASE or
querying the header page, even if this transaction in MON$TRANSACTIONS
is marked as active (MON$STATE = 1?)
- Why is there a difference regarding transaction counters when querying
MON$DATABASE and the header page?


Thanks a lot!



--
Best Regards,
Thomas Steinmaurer
LogManager Series - Logging/Auditing Suites supporting
InterBase, Firebird, Advantage Database, MS SQL Server and
NexusDB V2
Upscene Productions
http://www.upscene.com
My blog:
http://blog.upscene.com/thomas/