Re: Inheritance in Postgresql ?

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От ABBAS SHAKEEL
Тема Re: Inheritance in Postgresql ?
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Msg-id a498e47a0912152301j49d2fac4u4224c16e8562306c@mail.gmail.com
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Ответ на Re: Inheritance in Postgresql ?  (Scott Marlowe <scott.marlowe@gmail.com>)
Ответы Re: Inheritance in Postgresql ?
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Thanks Scott

you are right . It inherits structure only and i don't know whether to call to it an advantage or disadvantage that it query the children table as well while select. But in case of insert and update this concepts takes a new turn. 
How inheritance effect data?
 Can you please briefly compare concept of inheritance in Postgres and JAVA, as my mind is trying to compare this with already  stored concept in mind about inheritance ;)

On Wed, Dec 16, 2009 at 11:51 AM, Scott Marlowe <scott.marlowe@gmail.com> wrote:
On Tue, Dec 15, 2009 at 11:36 PM, ABBAS SHAKEEL
<shakeel.abbas.qau@gmail.com> wrote:
> Hello
> I am not an expert for database but rarely design database for Web and IVR
> applications.
> Today I wonder if there is any practical advantage of inheritance of Tables.
> Lets take the same example that is commonly referred.
>
> CREATE TABLE cities (
>     name            text,
>     population      float,
>     altitude        int     -- in feet
> );
>
> CREATE TABLE capitals (
>     state           char(2)
> ) INHERITS (cities);
>
> Capital table inherit attributes from Cities but no data. I am confused with
> concept of inheritance in postgres.
>
> In These tables what i was supposing is inheritence as that in JAVA. but its
> seems to be  a different scene.

The child table inherits structure from the parent, the parent then
allows you to retrieve data from it and the children together.



--
Best Regards
Shakeel Abbas

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