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what is the Best Index for a column which can be a null [message #325115] Thu, 05 June 2008 01:18 Go to next message
ramanajv1968
Messages: 168
Registered: December 2005
Location: HYDERABAD
Senior Member
Hi,

What is the best type of Index on a column in which 30-40 % of the values can be null and 10-25% can be a duplicate values and remaing a distinct.

Thanks
Re: what is the Best Index for a column which can be a null [message #325116 is a reply to message #325115] Thu, 05 June 2008 01:22 Go to previous messageGo to next message
Frank
Messages: 7880
Registered: March 2000
Senior Member
Since you typically would not want to use the index in case of a null (not distinguishing enough), you can do with a regular index.
Re: what is the Best Index for a column which can be a null [message #325118 is a reply to message #325115] Thu, 05 June 2008 01:26 Go to previous messageGo to next message
Michel Cadot
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Registered: March 2007
Location: Nanterre, France, http://...
Senior Member
Account Moderator
It depends of your queries and DML, number of rows, of distinct values.

Regards
Michel
Re: what is the Best Index for a column which can be a null [message #325163 is a reply to message #325115] Thu, 05 June 2008 03:57 Go to previous message
ramanajv1968
Messages: 168
Registered: December 2005
Location: HYDERABAD
Senior Member
Thank you all,

A regular index is served my purpose.

Thanks,
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