Re: subqueries vs. separate queries

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От Guy Fraser
Тема Re: subqueries vs. separate queries
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Msg-id 401985B5.2030307@incentre.net
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Ответ на subqueries vs. separate queries  (CSN <cool_screen_name90001@yahoo.com>)
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CSN wrote:

>Is there much difference between using subqueries and
>separating out them into separate queries?
>
>
That would depend on what results your expecting, and how you intend on using the results.

For example if you want all the data in a single statement, you can't break it up, but the request will likely use more
resourcesto complete. 
If your application can cut and paste the data from multiple transactions, then simple queries may need less resources
tocomplete, but remember that your application will require resources to cut and paste the results as well. 

I have written a number of PHP functions that uses an array the results of a query to generate formatted html tables,
graphsand statistical information. It is easiest to use a single complex query with subqueries, but it is possible to
'fake'a complex query by 'stacking' multiple results into an array. 

Hope that helps.






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