Drill Down Subreport Problem

rbuser

I have a huge selection of reports that are part of a product my company
recently purchased. I don't know what version of ReportBuilder they were
originally written in but we are now using version 7. The report I'm having
problems with has a drill-down subreport that shows additional information
about each detail line. The report works except when I drill-down. Then I
see the drill-down information for the first detail for all drill-downs. The
OpenDataSet event is only firing once. It seems to me it should fire every
time a new drill-down is opened.

Users have a huge amount of freedom to specify the filters and sort orders
for this report. The SQL is generated for the queries that retrieve the data
so a master/detail setup is not possible. What am I missing here? I'm new to
ReportBuilder but I'm begining to get the hang of it. Assuming I have the
correct source I can't imagine how this report every worked. Any ideas?

Craig Jensen
PowerQuest Corporation

digitalmetaphors

RB provides the capability to not fire detail querys for every master
record. This is very slow and this is how Delphi implements parameter query
linking. Is this a DADE report (Data Access Development Environment or
commonly known as the Data tab in the designer). If so, DADE creates a
special detail query such that it contains all records for all masters in
the report, ordered carefully. The order is important because the report
engine can traverse the detail dataset in order. When the key linking value
changes in the detail dataset, then the report engine knows that it can
begin printing the next set of detail records for the next master record.
This is much faster than Delphi query linking.

The drill down behavior you describe sounds like a custom drill down. Are
there any event handlers associated with this report? By default it should
drill down only the subreport that you've selected. I remember in the past
that we worked on helping a few customers implement alternative drill down
behaviors, such as toggling expand all capabilities. Compare the output of
the main reports demo #152 which implements DrillDown using our native
inplementation to this report you have inherited.


Cheers,

Jim Bennett
Digital Metaphors

rbuser

That sheds much light on the behavior I was seeing. I think I know how to
proceed at this point. For some reason the code was attempting to just query
the data for the related master record. This actually makes the code
simpler. Thanks for the help.

Craig Jensen

rbuser

This is not a DADE report. It uses two TppJITPipelines to try and do query
parameter linking. The timing of ReportBuilders events must have changed and
now the report no longer works. Is it even possible to do query parameter
linking with ReportBuilder? I've seen some of your tutorials and they use
master/detail linked tables. My SQL is dynamically generated and the detail
query needs to know the value of the linking field. Can this be setup in
ReqortBuilder?

Craig Jensen

digitalmetaphors

Yes, you can use Delphi parameter linking on queries, although it is very
slow. Here is an example which sets the parameters manually as an
alternative:

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


Cheers,

Jim Bennett
Digital Metaphors

rbuser

This is a good example but remember I'm talking about a drill down report.
Isn't there any way to query the data when the drill down is expaned? Why
isn't there an OnDrillDown or OnExpand event?

Craig

nardmoseley

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


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Nard Moseley
Digital Metaphors
http://www.digital-metaphors.com