🚀 go-pugleaf

On Thu, 26 Feb 1998 21:43:50 -0500, Peter Rorlick <Peter@InjuryTracker.com>
wrote:

>Ken Mayer wrote:
>
>> Try just using a query object, and setting the SQL property to
>> something
>> like: "select * from customer".
>> Then, set the rowset (of the query)'s indexName property to whatever
>> index you need.
>
>Ken, I did some bench-testing yesterday on this issue. The local SQL
>engine seems to ignore the opportunity of optimizing a relation through
>the utilization of an existing index.  My test was to create two tables
>(customers and orders). I started with no indexes in the Customers
>table. I wrote a program that did an INNER JOIN from Orders to Customers
>(both tables have a Customer_ID field) using a Query object. A loop then
>printed to the results pane
>? Orders.OrderNum, Customers.Name
>for every row in the rowset.  It took 9 seconds.
>Then I built a Customers index tag on the Customer_ID field.
>Quit from VdB, started up again and ran the loop program. It took 9
>seconds again.
>
>My conclusion: Either I'm missing something or the local SQL engine is
>passing up a golden opportunity to optimize the query.

More information, please:

What type of local table? dBASE or Paradox? What level table?

What type of index was used? Primary or secondary? Single- or multi-column?
dBASE expression index?

**************************************************************************
Steve Koterski
Borland International, Inc.
http://www.borland.com/delphi
(Remove the "SPICEDHAM2" from the address. Death to spam-bots!)