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Re: How are NULLS stored on disk for PG 7.4? - Mailing list pgsql-general

From Bruce Momjian
Subject Re: How are NULLS stored on disk for PG 7.4?
Date
Msg-id 200401122343.i0CNhw527868@candle.pha.pa.us
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In response to How are NULLS stored on disk for PG 7.4?  (Arnold Mavromatis <A.Mavromatis@bom.gov.au>)
Responses Re: How are NULLS stored on disk for PG 7.4?
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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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