I believe that it is incorrect that it will intersect indexes.
I understand that some people think this might be preferable, but I do not 
believe this logic has ever been coded in.

-----Original Message-----
From: Charles Stevenson <stevenson.c...@gmail.com>
To: U2 Users List <u2-users@listserver.u2ug.org>
Sent: Tue, Oct 25, 2011 3:08 pm
Subject: Re: [U2] UniBasic Question

RetrieVe will use an index if it can, regardless of the order of the 
election criteria (& if not select list is already active).
etrieVe will now do intersections of index reults if 2 indexed 
election criteria are specified.
'm not sure when or how good it does that.
O.OPTIMIZE can override these attempts by RetrieVe.
O.INDEX will prevent indexes being used.
On 10/25/2011 5:00 PM, Steve Romanow wrote:
 I think we are bike-shedding this now :)

 I seem to recall that if the indexed field is _before_ the non indexed
 field, its benefit is not lost.  I have not looked close at that in a
 long time.

 On Tue, Oct 25, 2011 at 5:42 PM, Woodward, Bob
 <bob_woodw...@k2sports.com>  wrote:
> Add a second selection criteria and the benefit of the index is washed
> out.
> -----Original Message-----
> From: u2-users-boun...@listserver.u2ug.org
> [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Charles
> Stevenson
> Sent: Tuesday, October 25, 2011 2:39 PM
> To: U2 Users List
> Subject: Re: [U2] UniBasic Question
> True on UV, too.
> Compare output of these using EXPLAIN keyword:
> LIST FILE WITH indexed_field = "soemthing"  EXPLAIN
> LIST FILE WITH indexed_field = "soemthing"  EXPLAIN  NO.INDEX
> Or forget EXPLAIN, but do it with a large file and notice the speed
> differnce.
> On 10/25/2011 4:29 PM, charles_shaf...@ntn-bower.com wrote:
>>>> I don't know if I agree that SELECT is faster.  If you are using
>>>> indexed fields, SELECT is definitely not the good choice.
>> Are you saying that when there is an index, the system does not need
> to
>> read the record at all?  It just gets the SELECT list from the index?
> Is
>> this only true in Unidata?
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