I have never received an answer to this question, though I've asked many people. Hopefully somebody can help!

For performance reasons, I always create indexes on "NUMBER" datatype columns. This is because I thought that it was faster & more efficient.

Is this correct?

Is it better to index on NUMBER type datacolumns, or is there no difference between them and VARCHAR/CHAR type data columns when indexing?

And, in continuation, what is the best datatypes to index on? Does it matter at all? (Obvoiusly you can't index on BLOB types, but other than those...)

thanks much!