How smart is the 'select' statement in QTP ?

[Blue]

G'day Richard.

Have you thought about splitting the data into two tables, current and
history?  That would reduce the search set.

Are you utilizing FIND or SELECT?  If FIND mode it should only retrieve
those rows where the index key criteria is met.  If SELECT mode it may do a
full table scan.

Regards,
Blue

BTW, any work for an old PowerHouse guy in NZ?

> -----Original Message-----
> From: powerh-l-admin@cube.swau.edu
> [mailto:powerh-l-admin@cube.swau.edu]On Behalf Of Latimer, Richard
> Sent: Wednesday, September 05, 2001 3:51 PM
> To: PowerHouse List (E-mail)
> Subject: How smart is the 'select' statement in QTP ?
>
>
> Listland,
>
>
> We make extensive use of date ranged records in our billing
> application - eg
> we record that a particular aeroplane was owned by customer a
> from 1 January
> 1993 to 30 July 1997 and customer b from 31 July 1997 to < some
> date well in
> the future>.  This record is indexed on the aircraft registration
> (ascending) and then the applies from date (descending). Code in the
> maintenance screens ensures that there is only ever one 'active'
> record per
> aircraft.
>
> Lookups to get the customer for a particular flight are done by linking to
> the aircraft registration and then selecting the record where the date of
> flight is between the applies from and applies to date.  There was an
> implicit assumption that the 'select' would not need to continue scanning
> the file after the 'first' record since it's conditions would have been
> satisfied . . . however I suspect this is not the case.
>
> To date this method has worked well and run times are reasonable
> but we are
> looking to extend the technique to another lookup - in this case
> the runway
> and weather conditions applicable at the destination airport of a flight.
>
> Our most traded aircraft has had 30 owners in the 10 years we keep so even
> in the worst case the select only has to plough through that many records.
> The new scenario has the potential to generate that many per day! !
>
>
> My question is whether the select statement is smart enough to
> realise that
> the date is indexed / sorted and that it can stop looking after
> it has found
> the right 'handful' of records. ?
>
> Alternatively does anyone have a better idea for handling the lookup ?
>
>
> We are PowerHouse 6.07 on DB2/400
>
>
> tia
>
> Richard Latimer
> Wellington MIS Manager
> Airways New Zealand
> Ph +64 4 471 4744
> Fax +64 4 471 0395
>
>
>
>
>
>
>
>
>
>
>
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