Re: Do Views execute underlying query everytime ??

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От Matthew Nuzum
Тема Re: Do Views execute underlying query everytime ??
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Msg-id f3c0b4080506210745e9a9bb0@mail.gmail.com
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Ответ на Do Views execute underlying query everytime ??  (Amit V Shah <ashah@tagaudit.com>)
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On 6/21/05, Amit V Shah <ashah@tagaudit.com> wrote:
> Hi all,
...
> I am thinking of having a solution where I create views for each screen,
> which are just read only.
>
> However, I donot know if the query that creates the view is executed
> everytime I select something from the view. Because if that is the case,
> then I think my queries will again be slow. But if that is the way views
> work, then what would be the point in creating them ..
>
> Any suggestions, helps --

They do get executed every time. I have a similar issue, but my data
does not change very frequently, so instead of using a view, I create
lookup tables to hold the data. So once a day I do something like
this:
drop lookup_table_1;
create table lookup_table_1 as SELECT ...;

In my case, rows are not deleted or updated, so I don't actually do a
"drop table..." I merely add new records to the existing table, but if
your data changes, the drop table technique can be faster than doing a
delete or update.

--
Matthew Nuzum
www.bearfruit.org

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