Performance Difference between NUMERIC and VARCHAR2 attribute

Hi all

Does anyone have real-world experience (not something you read) with regards to, whether a NUMERIC column will provide performance improvement over VARCHAR2 column?

Taking into considreration :
- using column in a comparison

• file storage
• index creation on column

My brief test shows no improvement

If a numeric column provides better performance in a predicate clause, would you then create a surrogate for the varchar column that is the PK?

Thanks in adv. for you help

tony

_____       ________ / ___|Tony Jambu, Database & Web Consultant
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