Re: Compute attr_needed for child relations (was Re: inherit support for foreign tables) - Mailing list pgsql-hackers

From Etsuro Fujita
Subject Re: Compute attr_needed for child relations (was Re: inherit support for foreign tables)
Date
Msg-id 53FD3F47.2090706@lab.ntt.co.jp
Whole thread Raw
In response to Re: Compute attr_needed for child relations (was Re: inherit support for foreign tables)  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
(2014/08/27 11:06), Tom Lane wrote:
> Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp> writes:
>> (2014/08/27 3:27), Tom Lane wrote:
>>> I looked this over, and TBH I'm rather disappointed.  The patch adds
>>> 150 lines of dubiously-correct code in order to save ... uh, well,
> 
>> Just for my study, could you tell me why you think that the code is
>> "dubiously-correct"?
> 
> It might be fine; I did not actually review the new
> adjust_appendrel_attr_needed code in any detail.  What's scaring me off it
> is (1) it's a lot longer and more complicated than I'd thought it would
> be, and (2) you already made several bug fixes in it, which is often an
> indicator that additional problems lurk.

Okay.

> It's possible there's some other, simpler, way to compute child
> attr_needed arrays that would resolve (1) and (2).  However, even if we
> had a simple and obviously-correct way to do that, it still seems like
> there's not very much benefit to be had after all.  So my thought that
> this would be worth doing seems wrong, and I must apologize to you for
> sending you chasing down a dead end :-(

Please don't worry yourself about that!

Thanks,

Best regards,
Etsuro Fujita



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