Re: Identity projection

Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>

From: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
To: tgl@sss.pgh.pa.us
Cc: pgsql-hackers@postgresql.org
Date: 2012-09-14T07:26:04Z
Lists: pgsql-hackers
Although I said as following, the gain seems a bit larger... I'll
recheck the testing conditions...

> > Another point here is that the projection code already special-cases
> > simple projections, so it's a bit hard to believe that it's as slow as
> > you suggest above.  I wonder if your test case is confusing that
> > optimization somehow.
> 
> The whole table is on memory and query is very simple and the
> number of columns is relatively larger in this case. This is
> because I intended to improve retrieving a large part of
> partitioned table with many columns.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center