Re: Views- Advantages and Disadvantages

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От Joshua D. Drake
Тема Re: Views- Advantages and Disadvantages
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Msg-id 46426E2D.8030706@commandprompt.com
обсуждение исходный текст
Ответ на Re: Views- Advantages and Disadvantages  (Brent Wood <b.wood@niwa.co.nz>)
Ответы Re: Views- Advantages and Disadvantages  (Michael Glaesemann <grzm@seespotcode.net>)
Re: Views- Advantages and Disadvantages  (Brent Wood <b.wood@niwa.co.nz>)
Список pgsql-general
Brent Wood wrote:
> Ashish Karalkar wrote:
>> Thanks Brent for your replay,
>>
>>
>> What about the Disadvantages, Performance issues?
>
> As far as I'm aware, performance is the only real disadvantage.

What performance are we talking about here? Executing from a view
although has *some* overhead, I don't even know that it is worth
considering in most cases.

Joshua D. Drake

>
> I tend to break DB design into stages:
>
> ER modelling to define the entities/relationships the DB needs to
> store/represent
> Normalize this to maximise data integrity & minimise duplication/redundancy
> De-normalise to meet performance & access requirements.
>
>
> In the latter stage, views are generally used, unless there are
> performance restrictions,
> when a de-normalised schema may be applied.
>
> Cheers,
>
>  Brent
>
> ---------------------------(end of broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
>       choose an index scan if your joining column's datatypes do not
>       match
>


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