Re: FOR KEY LOCK foreign keys

Excerpts from Noah Misch's message of vie mar 11 12:51:14 -0300 2011:
> On Fri, Feb 11, 2011 at 02:13:22AM -0500, Noah Misch wrote:
> > Automated tests would go a long way toward building confidence that this patch
> > does the right thing.  Thanks to the SSI patch, we now have an in-tree test
> > framework for testing interleaved transactions.  The only thing it needs to be
> > suitable for this work is a way to handle blocked commands.  If you like, I can
> > try to whip something up for that.
> [off-list ACK followed]
> 
> Here's a patch implementing that.  It applies to master, with or without your
> KEY LOCK patch also applied, though the expected outputs reflect the
> improvements from your patch.  I add three isolation test specs:
> 
>   fk-contention: blocking-only test case from your blog post
>   fk-deadlock: the deadlocking test case I used during patch review
>   fk-deadlock2: Joel Jacobson's deadlocking test case

Thanks for this patch.  I have applied it, adjusting the expected output
of these tests to the HEAD code.  I'll adjust it when I commit the
fklocks patch, I guess, but it seemed simpler to have it out of the way;
besides it might end up benefitting other people who might be messing
with the locking code.

> I only support one waiting command at a time.  As long as one commands continues
> to wait, I run other commands to completion synchronously.

Should be fine for now, I guess.

> I think this will work on Windows as well as pgbench does, but I haven't
> verified that.

We will find out shortly.


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Álvaro Herrera 
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