If I indexed @ID, I would always include nulls in the index. Two reasons:

1) There should never be a null @ID

2) The reason you shouldn't index nulls is because you may have many records 
with a null value, so you will end up with a huge record in your index. Bad... 
But with @ID you'll only have one value so the argument against indexing nulls 
is invalid.

Cheers,
Wol

-----Original Message-----
From: [email protected] 
[mailto:[email protected]] On Behalf Of Martin Phillips
Sent: 30 January 2009 10:27
To: [email protected]
Subject: Re: [U2][UD] Index for @ID (IBM documentation)

Hi,

> Martin, are you sure?  I would expect the query optimizer to see
> the <= and cancel the use of the index.

Unless I mis-typed my posting (I didn't keep it), it is fine because the
overall condition is not satisfied by a null item.


Martin Phillips
Ladybridge Systems Ltd
17b Coldstream Lane, Hardingstone, Northampton, NN4 6DB
+44-(0)1604-709200
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