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Creating Indexes on Number Columns

Deepika Saxena
Ranch Hand

Joined: Jul 05, 2009
Posts: 59
is there any performance overhead creating indexes on a table columns, whose data type is other than number or interger? i mean if we have a table Emp with the following structure and assume that eno, ename both will only accept unique values. in this case , what is the recommended way to create index? is it on eno or ename? i read that indexes on numbers will have better performance over the indexes, which are created on characters. could any body please explain the reason behind this.
Jeanne Boyarsky
internet detective

Joined: May 26, 2003
Posts: 30512

The fastest index is the one that is used the most. Do you have more queries/joins by number or name? I would imagine number making it the best choice of an index.

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subject: Creating Indexes on Number Columns