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DATACOM - Master Key, Natvie Key and Index

 
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latron

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Joined: 10 Dec 2008
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Location: CHENNAI

PostPosted: Wed Dec 17, 2008 4:35 am    Post subject: DATACOM - Master Key, Natvie Key and Index
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Having understood, that Native Key Dictates the Physical Sequence in which data is stored in Data Area. Would it perform better if the Index is created based on Native Key And my 'where' clause also only the columns defined in Native Key ?

Thank you...
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dick scherrer

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Joined: 23 Nov 2006
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PostPosted: Wed Dec 17, 2008 5:58 am    Post subject:
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Hello and welcome to the forum,

Suggest you spend some time in the DBA Admin Guide. I believe your understanding will benefit.

In many tables (even most tables), the master key and the native key are the same key. There are very often multiple other keys to the data in the table - either simple or complex keys.

Proper definition of the keys depends on how the data will be used.

Quote:
Would it perform better if the Index is created based on Native Key And my 'where' clause also only the columns defined in Native Key ?
Performance is best when the WHERE predicate(s) is/are completely satisfied by the column(s) of some particular key.
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latron

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PostPosted: Wed Dec 17, 2008 6:56 am    Post subject:
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That's clear. Thank you.
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