Re: Physical row sizes.

On Wed, 30 Nov 2005 18:56:22 -0800, DaLoverhino wrote:

>
> Finally, I'd like to index name, address, description by whether it's
> 'null' or 'non-null'. I want to delete rows with null values to them.
> Is there a special null/non-null index type which I can use? I don't
> want the overhead of a 'real' index.

Indexes do not include nulls. However, you can convert a null to a non-null using the NVL or NVL2 functions and you could create Function Based Index based on that if you are using 9i Enterprise or 10g SE1+ (Credit to Tom Kyte)

But - indexes are often overrated. The overhead they create - even on pure selects - can overwhelm their performance benefits in some situations. Recommended reading: Tom Kyte's latest book (published by Apress) as well as a number of publications by other Oaktable.net members.

Is there really a need to do the deletes based on an index? Or is this a pipe-dream carried over from experience with other RDBMSs?

-- 
Hans Forbrich                           
Canada-wide Oracle training and consulting
mailto: Fuzzy.GreyBeard_at_gmail.com   
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