Two pass and performance

rbuser

Hi, i have a performance question. I don't fully understand when i need
one or two passes. Does it affect the report performance?
I'm asking that because i have a very heavy report. It takes almost 2
minutes in terminate, and after that if i choose to export, i have to
wait another 2 minutes.
But, if i set the report to two pass, after the data is displayed the
cursor remains in hourglass for a big while too.
What am i doing wrong? How can i have my report time remain in the two
original minutes only?
thanks
--
Guillermo Castaño Acevedo
Gerente de Sistemas - Grupo Millennium Ltda
GuillermoC@GrupoMillennium.com
www.GrupoMillennium.com

digitalmetaphors

You'll need a twopass report if you have LookAhead totals, or need to know
the page total count, when the first page is sent to the output device.


Cheers,

Jim Bennett
Digital Metaphors

rbuser

But does the twopass fetches the database data twice or only on the first
pass? My exact question: is the second pass heavy-time consuming?
thanks

digitalmetaphors

The data is traversed in the first pass and then again in the second pass.
The dataset stays open from the start of the first pass to the end of the
second pass.


Cheers,

Jim Bennett
Digital Metaphors

rbuser

Sorry, but i must take a dessing decision:
so if i have a master/detail report all the details are fetched again?
thanks

digitalmetaphors

If you are using Delphi master-detail linking and not DADE linking, then
yes, the detail queries will be re-executed. DADE is optimized so that one
query is sent to get all of the detail records for the report, in the proper
order based on the order of the master records.


Cheers,

Jim Bennett
Digital Metaphors

rbuser

Thanks, it solved all my questions.