Re: Terrible performance on wide selects

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От Dann Corbit
Тема Re: Terrible performance on wide selects
Дата
Msg-id D90A5A6C612A39408103E6ECDD77B8294CD866@voyager.corporate.connx.com
обсуждение исходный текст
Ответы Re: [PERFORM] Terrible performance on wide selects  (Hannu Krosing <hannu@tm.ee>)
Список pgsql-hackers
[snip]
> For the disk case, why not have the start of the record
> contain an array of offsets to the start of the data for each
> column?  It would only be necessary to have a list for
> variable fields.
>
> So (for instance) if you have 12 variable fields, you would
> store 12 integers at the start of the record.

You have to store this information anyway (for variable length objects).
By storing it at the front of the record you would lose nothing (except
the logical coupling of an object with its length).  But I would think
that it would not consume any additional storage.

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