"Josh Berkus" <josh@agliodbs.com> writes:
> Postgres terminated my back-end connection to the server when it
> reached the VACUUM statement.
> Next, I reconnected. I was quite surprised to discover that Postgres
> had *not* rolled back the changes made by the function before it
> crashed.
Yeah. The problem here is precisely that VACUUM does internal commits
--- so it committed your function's earlier changes too. When you
returned from the VACUUM, the function's execution context was gone
as a byproduct of post-commit cleanup. Oops. VACUUM is disallowed
inside functions as of 7.3 to prevent this problem.
I don't think you need to be too worried about database corruption
as a result of this experiment, fortunately.
regards, tom lane