Re: How is statement level read consistency implemented?

Roberts, Jon wrote:

> Back to PostgreSQL, when a vacuum is issued, the old deleted rows are
> removed.  This can be done with the autovacuum feature or manually.
>
> -Does vacuum make sure there are no long running queries referencing the
> deleted rows before it attempts to remove the old rows?

It does.

> -With autovacuum, does it skip these rows still being referenced in a
> transaction or does it wait?

It skips them, the idea being that a future vacuum will remove them.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
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