If we want to export a Master/Detail grid we get an error: "Out of memory". This happens even with small datasets. Attached is a sample Application.
Master-Detail - Large memory consumption when exporting expanded master rows
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Hello Oliver,
Thank you for sharing your sample project. This behavior looks strange as the number of detail clones is not very large. It may take us some time to find an appropriate solution.
Hello Paulo,
thanks for the quick fix. I no longer get the "Out of memory" exception. But it takes a really long time to export grids with a master-detail relationship. I.e. 5000 records with each 3 detail records weren't finished after 1 hour, then i aborted the process.
To my regret, we were not able to overcome this behavior yet. In fact, it can be reproduced without export routines. By calling "cxGrid1DBTableView1.ViewData.Expand(True)". We have to create 5000 DataController components with all their columns and data structure and this takes much time.
I see… that's a pity. With the data volume of our customers the export function will not be usable with a master-detail-grid.
One suggestion: if i call "cxGrid1DBTableView1.ViewData.Expand(False)" the full expansion is very fast. We almost only have one Detail-View.
If i understand correctly the "ARecurse" parameter is responible for expanding the detail views. But since there are no detail views to expand, shouldn't it be possible to only create the Datacontrollers when you need to?
Meaning in our case the expansion before the export should work as fast as the expanion with "ARecurse" = false.
The exporting mechanism uses a different expanding approach. However, in general this approach might work. I've created a separate ticket on your behalf (T856641: Exporting detail views takes long time) to investigate if it is possible to make the export routine faster.
I am not sure that we will be able to offer a solution in the near future, but we will try.