Re: relation_byte_size()

From: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: sailesh(at)cs(dot)berkeley(dot)edu
Cc: pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: relation_byte_size()
Date: 2003-12-18 03:46:58
Message-ID: 200312180346.hBI3kwk29136@candle.pha.pa.us
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Patch applied. Thanks.

---------------------------------------------------------------------------

Sailesh Krishnamurthy wrote:
>
> Hackers
>
> Here is the definition of relation_byte_size() in optimizer/path/costsize.c:
>
> ----------------------------------------------------------------------
> /*
> * relation_byte_size
> * Estimate the storage space in bytes for a given number of tuples
> * of a given width (size in bytes).
> */
> static double
> relation_byte_size(double tuples, int width)
> {
> return tuples * (MAXALIGN(width) + MAXALIGN(sizeof(HeapTupleData)));
> }
>
> ----------------------------------------------------------------------
>
> Shouldn't this be HeapTupleHeaderData and not HeapTupleData ?
>
> (Of course, from a costing perspective these shouldn't be very different but ...)
>
> --
> Pip-pip
> Sailesh
> http://www.cs.berkeley.edu/~sailesh
>
>
>
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