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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

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

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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

Frank
Messages: 7901
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.

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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

Michel Cadot
Messages: 68733
Registered: March 2007
Location: Saint-Maur, France, https...

Senior Member
Account Moderator

It depends of your queries and DML, number of rows, of distinct values.

Regards
Michel

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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

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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