Performance gain ?

We have an Package with constant definitions. (about 1400 constant)
A lot of views are using this constants and need about 8 sec to execute
One of the developers found a performance gain from about factor 4, if he substitutes the constant in a view with the value filled in the constant.
Do we have a possibility to get the performance gain without hardcoding the values?
Thanks in advance

You cannot reference packaged constants in SQL.
If you mean you are calling packaged functions which return constants then yes - I would expect there to be some small overhead for calling them from SQL (which could be magnified to noticeable levels of degradation if the function is called repeatedly). The overhead has been reduced somewhat with later versions of Oracle.
Of course there are also reasons why the optimizer might choose a more efficient plan when substituting literal values for unknown values up-front, since you provide more information to the optimizer.

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We are trying to test the effect of Multidimensional Clustering on the
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Regards,
Nilima Rodrigues

Hi,
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Performance Gain for IRIX servers if Personal flag is removed from magnus.conf file.

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That's a comment in the file. It has no effect at all.

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Markus and David,
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Markus:
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and
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Last edited by ScionicSpectre (2012-02-16 05:39:28)

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No performance gain when using local interfaces

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As I found these results a bit surprising, I changed the serialization method of my parameter object this way:
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<Fr?d?ric Chopard> wrote in message news:[email protected]..
So question is: is there an "undocumented optimization" of the stub/skel generated by weblogic which make local calls when callinga remote method inside the same VM ?
>
Some precisions:
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Regards

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