Re: Views - Under the Hood

One of the benefits of writing views instead of using SQL in your code,
is that any developer or developer tool can use the view.
So the DB developer writes the view and maybe define indexes that can
speed up the query and any developer of any software that uses the DB
can refer to the View instead of writing the SQL.
Moreover if sw developers use tools like ORMs those toolo can take
advantage of the View and write all the code to use them to speed up the
sw developer work.

Il 04/11/2010 20.24, Terry Lee Tucker ha scritto:
> On Thursday, November 04, 2010 15:03:49 Scott Marlowe wrote:
>> On Thu, Nov 4, 2010 at 12:43 PM, Terry Lee Tucker <terry(at)chosen-ones(dot)org>
> wrote:
>>> Greetings:
>>>
>>> Lately, I've begun using views quite often especially when queries for
>>> various reports, etc. become complicated. I am now wondering if there is
>>> a price to pay in terms of overhead for this. In truth, I don't really
>>> understand how a view works. I know that it takes on many of the
>>> attributes of a table, but is it a table? Is the data pulled together
>>> when one selects from the view or is it maintained as a table all along.
>>> Guidance to the ignorant appreciated...
>> In pgsql a view is actually a rule that fires off the original query
>> for you. So it's a simple wrapper, and is the same, for the most
>> part, as simply typing in the original query again. So, it's pretty
>> simple, and there's no real overhead to worry about.
> Thank you Scott! This is exactly what I needed to know...
>

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