Pipeline Master/Detail

rbuser

Hi,

I was wondering if there is any advantage to having
the pipelines Master/Detail as opposed to having
the underlying tables Master/Detail.

Is there any speed advantage?

I have a number of tables that are Master/Detailed
connected together. In code I create a pipeline
for each but I do not Master/Detail the pipeline.

Thanks

Joseph Gordon

digitalmetaphors

Delphi linking is slow. This is because the detail query fires each time the
master is traversed. With Datapipeline linking, you can construct a detail
query that returns all detail records for all masters, order by the master.
This way you can tell te report engine to just traverse the data using the
master datapipeline and master field links properties of the pipeline. This
is much faster because only one detail query is fired for each detail
pipeline. Here is an example:

http://www.digital-metaphors.com/tips/MagicMasterDetail.zip


Cheers,

Jim Bennett
Digital Metaphors

rbuser

Hi,

I my case I am using TTables (actually TwwTables) against a paradox
database. Would master the datapipe have any speed benifits for that?

Thanks,
Joseph Gordon

digitalmetaphors

It depends on how Infopower implemented the table linking. I suppose it is
faster than a TTable, but you're relying on paradox which is flaky in and of
itself most of the time. So many times I have lost Paradox data tables
because paradox gets itself corrupted so easily. Check out the BDE
alternatives listed on our website. Try searching google.com for benchmark
tests with different Delphi data connectivity components. About the fastest
you'll get for creating a master detail report, which all pages are going to
be generated, is to fire a single query for the detail records and use the
MasterFieldLinks and MasterDataPipeline of the pipes.


Cheers,

Jim Bennett
Digital Metaphors