Re: pageinspect: Hash index support

On 9/23/16 1:56 AM, Amit Kapila wrote:
> On Fri, Sep 23, 2016 at 9:40 AM, Peter Eisentraut
>> - hash_metap result fields spares and mapp should be arrays of integer.
>>
>
> how would you like to see both those arrays in tuple, right now, I
> think Jesper's code is showing it as string.

I'm not sure what you are asking here.

>> (Incidentally, the comment in hash.h talks about bitmaps[] but I think
>> it means hashm_mapp[].)
>>
>
> which comment are you referring here? hashm_mapp contains block
> numbers of bitmap pages.

The comment I'm referring to says

The blknos of these bitmap pages are kept in bitmaps[]; nmaps is the
number of currently existing bitmaps.

But there is no "bitmaps" field anywhere.

> In the above code, it appears that you are trying to calculate
> max_avail space for all pages in same way. Don't you need to
> calculate it differently for bitmap page or meta page as they don't
> share the same format as other type of pages?

Is this even useful for hash indexes? This idea came from btrees.
Neither the gin nor the brin code have this.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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