Re: How are NULLS stored on disk for PG 7.4?

From: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: Arnold Mavromatis <A(dot)Mavromatis(at)bom(dot)gov(dot)au>
Cc: "'pgsql-general(at)postgresql(dot)org'" <pgsql-general(at)postgresql(dot)org>
Subject: Re: How are NULLS stored on disk for PG 7.4?
Date: 2004-01-12 23:43:58
Message-ID: 200401122343.i0CNhw527868@candle.pha.pa.us
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Arnold Mavromatis wrote:
> Hi
>
> How are column files in a table that have been assigned null stored on disk
> in Postgresql 7.4?

Each row has a bitmap showing all the NULL values on that row.

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