Re: two phase commit

Ben <bench(at)silentmedia(dot)com> writes:
> I'm reading the description of PREPARE TRANSACTION, and I see this:
> "...its state is fully stored on disk, and there is a very high
> probability that it can be committed successfully..."

> What corner case reduces 2pc from "guaranteed" to "very high probability"?

Well, for example, someone drops a nuke on your data center ...

Barring hardware failure, OS failure, or irrecoverable database crash,
the only condition I can think of that would prevent COMMIT PREPARED
from succeeding is out-of-disk-space on the WAL drive. Which is a PANIC
condition anyway, and thus might be classed with database crashes,
although it's not irrecoverable so long as the admin can free up some
disk space.

regards, tom lane