Re: ALTER TABLE lock strength reduction patch is unsafe

Hi,

On 2014-02-26 07:32:45 +0000, Simon Riggs wrote:
> > * This definitely should include isolationtester tests actually
> >   performing concurrent ALTER TABLEs. All that's currently there is
> >   tests that the locklevel isn't too high, but not that it actually works.
> 
> There is no concurrent behaviour here, hence no code that would be
> exercised by concurrent tests.

Huh? There's most definitely new concurrent behaviour. Previously no
other backends could have a relation open (and locked) while it got
altered (which then sends out relcache invalidations). That's something
that should be tested.

> > * Why does ChangeOwner need AEL?
> 
> Ownership affects privileges, which includes SELECTs, hence AEL.

So?

Greetings,

Andres Freund

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