In Universe I have used the EXPLAIN keyword in the past to understand how the 
query will be processed.

You just add the keyword EXPLAIN to the end of your query statement.
The documentation says it for SQL statements but it seems to work on Universe 
SELECT statements.



Showing How a Query Will Be Processed (EXPLAIN)
Use EXPLAIN in a SELECT statement to display information about how the
statement will be processed, so that you can decide if you want to rewrite the 
query
more efficiently. You can also use EXPLAIN in an INSERT, UPDATE, or DELETE
statement, whenever it contains a WHERE clause or a query specification.
EXPLAIN lists the tables included in the query or WHERE clause, explains how 
data
will be retrieved (that is, by table, select list, index lookup, or explicit 
ID), and
explains how any joins will be processed. After each message, press Q to quit, 
or
press any other key to continue the query.
If a client program uses EXPLAIN in a SELECT statement, the statement is not
processed. Instead, an SQLSTATE value of IA000 is returned, along with the
EXPLAIN message as the message text.



Regards

Adrian Halid

-----Original Message-----
From: u2-users-boun...@listserver.u2ug.org 
[mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Wols Lists
Sent: Thursday, 8 November 2012 3:00 AM
To: u2-users@listserver.u2ug.org
Subject: Re: [U2] Multiple UniData Indexes in same select

On 07/11/12 17:18, Wjhonson wrote:
> What about Universe?
> 
imho, it just doesn't make logical sense in BASIC!

just do SELECTINDEX, READLIST, SELECTINDEX, READLIST and then manipulate it 
yourself.

Okay, that's more hassle, but IME the results of reading the index file always 
give me a sorted list, so doing a union or intersect of two sorted lists isn't 
that tricky.

Cheers,
Wol
> 
> -----Original Message-----
> From: Wally Terhune <wterh...@rocketsoftware.com>
> To: U2 Users List <u2-users@listserver.u2ug.org>
> Sent: Wed, Nov 7, 2012 9:05 am
> Subject: Re: [U2] Multiple UniData Indexes in same select
> 
> 
> No on UniBasic SELECTINDEX statement.
> 
> Not sure I'd call a change made at UniData 5.2 in June of 2000 as 
> 'news'. :-)
> 
> Wally Terhune
> Technical Support Engineer
> Rocket Software
> 4600 South Ulster Street, Suite 1100 **Denver, CO 80237 **USA
> t: +1 720 475 8055 **e: wterh...@rocketsoftware.com **w: 
> u2.rocketsoftware.com
> 
> 
> 
> -----Original Message-----
> From: u2-users-boun...@listserver.u2ug.org 
> [mailto:u2-users-boun...@listserver.u2ug.org]
> On Behalf Of Dave Laansma
> Sent: Wednesday, November 07, 2012 9:54 AM
> To: U2 Users List
> Subject: Re: [U2] Multiple UniData Indexes in same select
> 
> Excellent news.
> 
> However, is there a way to utilize two indexes with the SELECTINDEX 
> command in Unibasic?
> 
> Sincerely,
> David Laansma
> IT Manager
> Hubbard Supply Co.
> Direct: 810-342-7143
> Office: 810-234-8681
> Fax: 810-234-6142
> www.hubbardsupply.com
> "Delivering Products, Services and Innovative Solutions"
> 
> -----Original Message-----
> From: u2-users-boun...@listserver.u2ug.org
> [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Wally 
> Terhune
> Sent: Wednesday, November 07, 2012 11:47 AM
> To: U2 Users List
> Subject: Re: [U2] Multiple UniData Indexes in same select
> 
>>From the Using UniData manual:
> 
> Alternate Indexes in UniQuery Statement Prior to UniData 5.2, only one 
> index was used in the selection criteria of a UniQuery statement, even 
> if the selection criteria contained more than one indexed attribute. 
> UniQuery now uses all available indexes when processing a statement 
> containing selection criteria.Note: You cannot use an alternate index 
> with a LIKE clause when the comparative attribute is numeric.
> 
> Wally Terhune
> Technical Support Engineer
> Rocket Software
> 4600 South Ulster Street, Suite 1100 **Denver, CO 80237 **USA
> t: +1 720 475 8055 **e: wterh...@rocketsoftware.com **w:
> u2.rocketsoftware.com
> 
> 
> 
> -----Original Message-----
> From: u2-users-boun...@listserver.u2ug.org
> [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Doug Farmer
> Sent: Wednesday, November 07, 2012 7:35 AM
> To: U2 Users List
> Subject: [U2] Multiple UniData Indexes in same select
> 
> Good morning,
> 
> I should know this, but as the gray gets thicker, some of the old 
> knowledge seeps away.
> 
> If you have indexes on multiple attributes on a file in UniData AND 
> you include both of those indexed attributes in the same Select 
> statement, how does UniData know which index to use? Does it use both? 
> Neither?
> 
> Thanks in advance,
> 
> Doug
> --------------------------------------------------------
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