From: | Ron Johnson <ron(dot)l(dot)johnson(at)cox(dot)net> |
---|---|
To: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: Size of tuples |
Date: | 2006-10-10 01:21:17 |
Message-ID: | 452AF58D.8050506@cox.net |
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Thread: | |
Lists: | pgsql-general |
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On 10/09/06 19:10, Alex Turner wrote:
> I have a table whose definition is basically
>
> create table foo (
> a int,
> b int,
> c int,
> d date
> );
>
> and when fully populated, select relpages*8192::long/reltuples from
> pg_class
> where relname='foo';
> gives around 52. Why is it so wide when there are only 4*4=16 bytes of
> actual data?
http://www.postgresql.org/docs/faqs.FAQ.html#item4.5
23 row header (no OIDs)
+ 16 your row size
+ 4 page pointer
--
43
I'd guess that the extra 4 bytes is from the null bits, page
overhead, etc.
- --
Ron Johnson, Jr.
Jefferson LA USA
Is "common sense" really valid?
For example, it is "common sense" to white-power racists that
whites are superior to blacks, and that those with brown skins
are mud people.
However, that "common sense" is obviously wrong.
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