Re: Views- Advantages and Disadvantages

Thanks Brent for your replay,


What about the Disadvantages, Performance issues?


With Regards
Ashish...





----- Original Message -----
From: <woodb@niwa.co.nz>
To: "Postgres General" <pgsql-general@postgresql.org>
Cc: "Ashish Karalkar" <ashish.karalkar@info-spectrum.com>
Sent: Wednesday, May 09, 2007 1:24 PM
Subject: Re: [GENERAL] Views- Advantages and Disadvantages


>> On 5/9/07, Ashish Karalkar <ashish.karalkar@info-spectrum.com> wrote:
>>
>> Hello All,
>> Can anybody please point me to Advantages and Disadvantages
>> of using view
>
> Hi Ashish,
>
> There are several, but they are generally about implementing a more user
> friendly database from a well normalised structure.
>
>
> You can use views to do any or all of:
>
> act as a filter on fields or records which can be accessed by given users,
>
> act as a stored query to avoid writing a commonly used SQL,
>
> aggregate normalised tables into a single virtual table, so that access
> does not require as complex a join, thus it can hide the complexity of the
> database structure from applications or users.
>
> An example use is to have a view which provides only the current version
> of data from a database which stores multiple versions of the data.
>
> Cheers,
>
>  Brent Wood
>
>

----- Original Message -----
From: "Ashish Karalkar" <ashish.karalkar@info-spectrum.com>
To: "Andrej Ricnik-Bay" <andrej.groups@gmail.com>
Cc: "Postgres General" <pgsql-general@postgresql.org>
Sent: Wednesday, May 09, 2007 12:46 PM
Subject: Re: [GENERAL] Views- Advantages and Disadvantages


> Thanks Andrej
> for your replay
>
> I have found out some of them n are as follows, but  I want more reasons
> for not using views . I only got one
>
> Advantages:
>
>      1)  Permission to user can be given to access the database only
> through view containing specific data the user is authorized to see
>
>      2)       View  convert multiple table queries into single table
> queries
>
> 3)       Views give personalized view
>
> 4)       Views provide consistent unchanged image even if the underlying
> table columns changed.
>
>
>
> Disadvantages:
>
>
>
> 1)      Performance : If a view is defined by complex multitable
> query,then
> simple query against that view becomes a coplecated join, and it may take
> a
> long time to complete
>
>
>
>
>
>
>
>
> ----- Original Message -----
> From: "Andrej Ricnik-Bay" <andrej.groups@gmail.com>
> To: "Ashish Karalkar" <ashish.karalkar@info-spectrum.com>; "Postgres
> General" <pgsql-general@postgresql.org>
> Sent: Wednesday, May 09, 2007 12:08 PM
> Subject: Re: [GENERAL] Views- Advantages and Disadvantages
>
>
>> On 5/9/07, Ashish Karalkar <ashish.karalkar@info-spectrum.com> wrote:
>>> Hello All,
>> Hi,
>>
>>> Can anybody please point me to Advantages and Disadvantages
>>> of using view
>> The most obvious advantage (for me, anyway) is to restrict which
>> columns a user can see in a table.
>>
>> I'm sure there are others.
>>
>>
>>
>>
>>> With Regards
>>> Ashish...
>> Cheers,
>> Andrej
>>
>>
>> --
>> Please don't top post, and don't use HTML e-Mail :}  Make your quotes
>> concise.
>>
>> http://www.american.edu/econ/notes/htmlmail.htm
>>
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