TdaSqlBuilder in Master-Detail mode does not work...

rbuser

Hi

Does anyone have a simple rtm-example how to program a master-detail
relation using the TdaSqlBuilder-Object in RAP?
My report has a supreport with the detaildata on it. Every time the
masterrecord change the subreport should display the detaildata.

I tried to do that but the ApplyUpdates does not fire any refetch of data.

Thanks and best regards
Robert


Here my code:

// this is the initial code for the detail pipeline
procedure ReportBeforeOpenDataPipelines;
var lSQLBuilder : TdaSQLBuilder;
begin
lSQLBuilder := TdaSQLBuilder.Create(ppVGK_AKTIVITAETEN);
lSQLBuilder.Clear;
lSQLBuilder.SelectTables.Add('VGK_AKTIVITAETEN');
lSQLBuilder.SelectFields.AddAllFields;
lSQLBuilder.SearchCriteria.Add('VGK_AKTIVITAETEN', 'GELFNR', '=', '0');
lSQLBuilder.ApplyUpdates;
lSQLBuilder.Free;
end;

// this is the code using for the supreport-data
procedure SubReport1OnPrint;
var lSQLBuilder : TdaSQLBuilder;
begin
lSQLBuilder := TdaSQLBuilder.Create(ppVGK_AKTIVITAETEN);
lSQLBuilder.SearchCriteria[0].Value := Pipe['GELFNR'];
<< on this 'GELFNR' the data should be fetched, but nothing happend
lSQLBuilder.ApplyUpdates;
lSQLBuilder.Free;
end;

nardmoseley

There is no way to control the detail SQL for each master record, that is
not how the Data workspace linking is implemented. The Data workspace linkes
the datapipelines and generates special linking SQL for the detail dataview.
This results in a single detail SQL statement. Please see the article
below...

TdaSQLBuilder can only be used from an event of the main report that occurs
prior to the datapipelines being opened. I recommend using the
Report.BeforeOpenDataPipelines event.


-------------------------------------------
Tech Tip: Linking DataViews
-------------------------------------------

Overview
---------

Linking DataViews in the ReportBuilder Data workspace (DADE), requires that
the detail data be sorted by the linking fields. When DataViews are linked,
DADE generates special linking SQL for the detail DataView. The linking SQL
(Magic SQL) can be viewed by positioning the mouse over the DataView window
and pressing Ctrl + Left Mouse button. The results of the Magic SQL query
can be viewed by pressing Shift + Left Mouse button.

ReportBuilder's DataPipeline architecture includes support for linked data
traversal. Whenver the record position of the master data changes, the
traversal logic compares the master and detail field link values and then
determines where to locate the record position for the related detail data.
The linking logic will only work properly if the Database engine's collation
of the detail query result set is in sync with ReportBuilder's internaly
field link comparison logic.