No, you don't want to index on the ID because it is unique. That would be a
very inefficient index. If you created an i-descriptor that broke the ID into
several multi-valued parts, then it MAY help, but I don't think it is worth the
overhead.
Tom
-Original Message-
From: owner-u2-us
Okay, cool :) I thought I was going crazy when I read that and that my
knowledge of indexes was more bunk than it already is.
Thanks Tom!!!
--JJ
On Wed, Jan 28, 2009 at 1:52 PM, Tom Whitmore wrote:
> No, you don't want to index on the ID because it is unique. That would be a
> very inefficien
It's not going to speed everything up, just certain select statements. And
quite honestly, it's going to speed up certain select statements that are
not really kosher.
For example, if your application is full of select statements like SELECT
FILE WITH @ID = "ABCDEF", then you should probably re-w
> It's not going to speed everything up, just certain select statements.
And
> quite honestly, it's going to speed up certain select statements that
are
> not really kosher.
>
> For example, if your application is full of select statements like
SELECT
> FILE WITH @ID = "ABCDEF", then you should
Hi,
The most common use of an index on @ID is where the ids are a sparse set of
values and you want to find those in a specific range. For example, if I
have a file where the id is the date but not all dates are present, I might
want to do
LIST MYFILE WITH DATE >= "1 Jan 08" AND <= "31 Dec
Martin, are you sure? I would expect the query optimizer to see the <= and
cancel the use of the index.
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.org] On Behalf Of Kevin King
Sent: Friday, 30 January 2009 7:18 AM
To: u2-users@listserver.u2ug.org
Subject: Re: [U2][UD] Index for @ID (IBM documentation)
Martin, are you sure? I would expect the query optimizer to see the <= and
cancel the use of the index.
---
u2-users
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 Lan
t: 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
If you have access to a UV system, add EXPLAIN to the command line to see
what RetrieVe does.
On Thu, Jan 29, 2009 at 12:18 PM, Kevin King wrote:
> Martin, are you sure? I would expect the query optimizer to see the <= and
> cancel the use of the index.
---
u2-users mailing list
u2-users@li
Hi,
If you have access to a UV system, add EXPLAIN to the command
line to see what RetrieVe does.
Works fine for me, using the index.
Martin Phillips
Ladybridge Systems Ltd
17b Coldstream Lane, Hardingstone, Northampton, NN4 6DB
+44-(0)1604-709200
On Thu, Jan 29, 2009 at 12:18 PM, Kevin Ki
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