Re: relation_byte_size() - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: relation_byte_size()
Date
Msg-id 200312180346.hBI3kwk29136@candle.pha.pa.us
Whole thread Raw
In response to relation_byte_size()  (Sailesh Krishnamurthy <sailesh@cs.berkeley.edu>)
List pgsql-hackers
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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--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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