Preview is alright (showing 1 page only) but then prints continuous stream of empty pages ???!!

rbuser

Hey guys,

I have a report (who would have guessed?! ;-) and it shows just fine in the
preview. However, when I click the little print-button it starts to print a
continous stream of empty pages :-/

Has anybody seen this behaviour before and has found the cause?

During development I only sometimes printed a report trusting that the print
would be the same as the preview and I never had any errors like this. The
only thing changed since then is that we're now working on the
semi-production database and before on the test-database. I can't imagine
this has anything to do with it though...

What can cause a difference between the preview and the actual printing?

Any help is much appreciated.

Vince.

nardmoseley

------------------------------------------------------
Article: TroubleShooting: Report Prints Endless Pages
------------------------------------------------------

1. Check each report/childreport and make sure that the Report.DataPipeline
property is assigned OR AutoStop is set to True.

2. Try setting all Detailband.PrintHeight to phDynamic. It may be that you
have a fixed height detail band that is too large to print on a page.

3. As a test, try commenting out all event-handler code associated with the
report. Make sure that you are not manipulating the dataset in any manner,
while the report is generating. This can cause the report engine to get
lost.

4. Save the report under a new name and try incrementally simplifying it
until the issue goes away. Then incrementally add complexity until you
isolate the cause of the error.

If you still have an issue after performing the above steps, please create a
simple, minimal Delphi project and e-mail to support@digital-metaphors.com
in zip format.


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








--

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

rbuser

Hello again,

Sorry for the late reply, I haven't been working on this since last
monday...

I found out that I have code in the ppReportBeforePrint event. The code
loops through a dataset. That dataset has an AfterOpen and an AfterScroll.
In the AfterOpen and in the AfterScroll a query (depending on values from
the selected record in my main recordset) is activated that is required for
my subreport.

My problem disapears when:
A) I disable the line in the afterscroll where I activate the query for my
subreport
or
I delete the subreport completely.

Either is not a solution because I need my subreport.

Option A is strange because in that case the same recordset gets used for
every record in my main recordset (which is connected to the ppReport) and
it works...

I just heard that a new version is available which I am downloading right
now. Do you think the new version might solve this problem?

Regards,

Vincent.

rbuser

Unfortunately the update didn't help...

digitalmetaphors

Do not use the DataSet.AfterOpen and Afterscroll events. That is the
problem.

1. Below is an article on linking datasets. Try using one of the techniques
explained in the article. (The two techniques are mutually exclusive).

2. In general you should not have any event-handler code that manipulates
the datasets while the report is executing.

3. If you need to manually filter the detail dataset, use the master
DataPipeline OnRecordPositionChange event.




------------------------------------------------------
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

Hi Nard,

I deleted the subreport and instead used 3 ppDBMemo's since I was only using
the subreport to create 3 columns. Using the afterscroll seems to be okay
with this solution.

Thanks for your help again,

Vinz.