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mysql views

     
1:21 pm on Mar 27, 2010 (gmt 0)

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Hello,
I really don't understand the usage and advantages of VIEWS.

I mean, as I got it, the views are non-indexed temp table that are dropped after the PHP script ends. Then what is the advantage of using it?
2:54 pm on Mar 27, 2010 (gmt 0)

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VIEWS are not temp tables, they are stored SELECT statements. Think of them as virtual tables.

When you reference a view, the stored select statement is executed. Views allow you to create complex queries that you can treat as a table. The underlying data remains in the tables referenced in the view definition. Indexes for those tables are still utilized.
2:41 pm on Mar 29, 2010 (gmt 0)

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what happens if 2 users run the same script at the same time? The view will be overwritten?
2:08 pm on Mar 30, 2010 (gmt 0)

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The view does not store any data. The two users see the same result set as if they had typed in the query directly.
9:19 am on Apr 7, 2010 (gmt 0)

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However with exclusive locks two users will never be able to run the same script simultaneously.
10:57 am on Apr 7, 2010 (gmt 0)

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SELECT statements don't acquire exclusive locks.