NO_EXPAND Hint

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NO_EXPAND Hint

Postby Raaj A » Fri Nov 02, 2012 5:52 am

Hi Tim,

What is exactly "NO_EXPAND" hint ? can we use "NO_EXPAND" hint permanently in a query to increase the efficiency of the sql query?

Thnaks
Raaj
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Re: NO_EXPAND Hint

Postby Tim... » Fri Nov 02, 2012 8:44 am

Hi.

The manual explains what is does:

http://docs.oracle.com/cd/E11882_01/ser ... SQLRF50502

Hints tell the optimizer to do something that it may not otherwise do. As a result, in some situations a hint may improve performance, in others is may reduce it. You should try not to use hints unless you have a documented case where it improves performance. Even then, you should attempt to remove them with subsequent patches and updates to see if the particular issue you faced has been resolved in the updated optimizer.

Cheers

Tim...
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Re: NO_EXPAND Hint

Postby Raaj A » Fri Nov 02, 2012 9:23 am

Thankyou so much.....
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Re: NO_EXPAND Hint

Postby Tim... » Fri Nov 02, 2012 11:03 am

:)
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