Subject OAT/OIT/OST questions
Author Fernando P. Nájera Cano

I have a few questions about the transaction numbers.

The documentation at says that
OST is normally the same as OAT.

* When could OST be different to OAT?
* Is it possible to simulate this situation (OST != OAT) by using isql?
If yes, how?
* If OST and OAT are different, which one is higher?

My current understanding is that OIT is always the lowest of the
three, and I think that OAT should be less or equal than OST.

* Is this true, then? OIT <= OAT <= OST

Also, given that OST is the oldest snapshot transaction:

* What happens if there is no current snapshot transaction?

* If the database had never had a snapshot transaction, would this
value be 1 (or 0) while OAT and OIT have moved on?

And one extra question:

* If I'm in the middle of a transaction and the network connection
breaks, what happens to the OAT/OIT/OST - in particular, does any of
them get stuck? If yes, for how long?

Thanks in advance for any help and/or links where I could find

Best regards,

Fernando Nájera