Re: [HACKERS] Bizarre coding in _bt_binsrch

> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Tom, I assume you have dealt with this, right?
> 
> >> I have been puzzling out the coding in _bt_binsrch() in
> >> backend/access/nbtree/nbtsearch.c, with an eye to speeding it up for
> >> the many-equal-keys case.
> 
> I tweaked the code to go faster in the equal-keys case, but Vadim later
> pointed out that what we *really* should do is force the algorithms to
> never consider two index keys equal (eg, by including the heap tuple id
> as the last part of the comparison key).  See his pgsql-hackers message
> dated 06 Jun 1999 21:32:36 +0800.  Getting the full benefit would
> require ripping out the BTP_CHAIN logic and doing some other major
> surgery, so I don't feel like I know the btree code well enough to
> tackle it.  It should be on the TODO list though:
> 
> * Include heap CTID in btree index keys, remove equal-key cruft from btree

Thanks. That's what I needed.

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