Error printing empty subreports...

rbuser

Hi,

In my application I'm using ReportBuilder 7.02 and Data Abstract. I have a
main report with 3 sub-reports (3 detail tables). When I try to print that
report I get the error "Expression expected but nothing found" when at least
one of the detail tables is empty for that master record. I've tried using
DataPipeline linking but I just can't seem to find a sollution...

Thanks in advance
Alexandre

nardmoseley

ReportBuilder supports two types of data linking. See the following article.

For the detail datapipelines you can set SkipWhenNoRecords to true/false to
determine the master record is skipped when there are no corresponding
detail records.

The datapipeline issues very simple commands on the dataset to which it is
connected: First, Next, Prior, Last, GetBookmark and GotoBookmark.


------------------------------------------------------
Tech Tip: Linking SQL Queries for Master/Detail Data
------------------------------------------------------

The following example shows two options for linking SQL queries to create a
master/detail relationship.

In this example, we are using Delphi's DBDemos data to create a
Customer/Order relationship. Thus we wish to link the Orders detail to the
Customer master.

I. Delphi Query Linking
------------------------

a. Set the detail TQuery.DataSource property to point to the master
query's TDataSource component.

b. In the SQL "Where" clause for the detail query use a ':' followed by
the linking field name from the master:

example
select *
from orders
where orders.CustNo = :CustNo

Now each time the master record position changes, the detail query will
automatically be refreshed with the correct result set.


II. RB DataPipeline Linking
-----------------------------

a. Set the detail DataPipeline.MasterDataPipeline to point to the master
DataPipeline.

b. Use the detail DataPipeline.MasterFieldLinks property to define the
linking relationship

c. In the SQL for the detail, retrieve all records and sort them by the
linking master field:

select *
from Orders
order by CustNo


Notes:

1. Using RB DataPipeline, each query is executed only a single time - thus
performance is much faster.

2. RB Professional and Enterprise Editions include a visual Data environment
for creating SQL queries, defining linking relationships, and creating
Ask-At-Runtime parameters. Using the RB tools you could create the above
linked queries in about 10 seconds.


--
Tech Support mailto:support@digital-metaphors.com
Digital Metaphors http://www.digital-metaphors.com





--
Nard Moseley
Digital Metaphors Corporation
www.digital-metaphors.com

rbuser

The problem doesn't seem to be caused by the linking (I'm using Delphi Query
Linking). I have 2 reports in order to print both sides of the same paper.
The first report has 1 detail table and it prints fine. The 2? report has
all the same settings enabled and 2 detail tables, and it causes the error.