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Diff.. Btn Table and View


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vamseepotti

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Joined: 21 Oct 2003
Posts: 45

PostPosted: Tue Feb 17, 2004 6:58 pm
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What is the exact difference between Table and View?
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mcmillan

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Joined: 18 May 2003
Posts: 1207
Location: India

PostPosted: Tue Feb 17, 2004 8:18 pm
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Table is a physical collection of your records.

View is just a select statement that uses the records in on or more physical table. It's an logical entity.

The main application of view is, it's exactly same as a table (with some restriction), but you can have records of more than one table in a single view.

The main usage of view is, you can hide some sensitive columns from your table to an end user, by allowing him to use only the view instead of your table.
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Johore

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Joined: 12 Sep 2003
Posts: 19

PostPosted: Wed Feb 18, 2004 9:06 am
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Table :

Is a physical entity containing data.It occupies a part of storage.

Views :

A virtual table consisting of an SQL select statement that accesses data
from one or more tables. A view never stores data. Its used when data
acceses needs to be restricted/regulated within groups. Also, a join
between different tables can be accessed using a view

Hth
johore icon_smile.gif
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anuradha

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Joined: 06 Jan 2004
Posts: 247
Location: Hyderabad

PostPosted: Thu Mar 04, 2004 10:02 pm
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hello vamsi,

just to add,here is some more info about views.This Article I read some time back.I thought it is useful.So I am posting it over here.

A view is a specific defined subset of the table in question.
we use a view for one of two reasons:

1) Ease of use. You can represent a complex statement in simpler
terms in case you want to make that information available in an
easier fashion. A good example is that a DBA can write a join of
the catalog tables as a view for the application programmers to
be able to provide their relevant information fast without much
knowledge of what the catalog tables are.

2) Selective security. You might want to limit full access to a
table, yet allow access to certain parts of it. A very good example
here is an employee table. The employee table would definitely not
be a good candidate for granting general access to update, or even
select because it would have confidential information that we would
not want just anyone to update or even see. But at the same time,
we would want to have the general public be able to see the relevant
parts of the employee table for things like employee listings and
office phone directories. Therefore, you would create a view
containing that relevant information the public should see and then
allow access to the view, while limiting access to the whole table.



THANKS AND REGARDS
ANU
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