Unreliable dynamic data attachments

[tomgr]

I have issues with dynamic data attachments being unreliable. I am testing with the two forms attached, Parent and Child. Parent has an ID field and a name, Child is to look up the name by the ID.

When I submit Parent forms, the data is seldom readable in the Child form. Sometimes the sync works once, so I get batch 1 Parent entries available. Then when I add more Parent entries, I usually don’t see these in Child form. Sometimes new entries can show up after 10-20 minutes. But very inconsistently. I really can’t trust this feature., which is a shame. And seems no logging available, either. Really hard to debug.

The Child form has an xml-external field with name parent, and per the documentation I’m referencing it in the calculation column. For entries that are synced to the device, it works, name shows up in Child form. So it shouldn’t be a syntax error in the form. I have activated Connected Projects as described, both on Parent and Child.

I mainly testing on Android (13, Play Service update July 2024) with KoboCollect v2024.1.3. Forms are on the EU toolbox instance. During testing, I am updating the forms manually by going into Download form. Sometimes it shows that the Child form has updates, and then I get new entries. But rarely. I experience the same unreliable behavior with these forms in Enketo.

If I delete the Child form and fetch it again, then it seems to bring the latest Parent data with it.

By the way, if I configure form update mode to Exactly match server, the smallest delay is fifteen minutes. How does that add up with fetching dynamic data, as documentation says there is a five minute delay? 3 5-minute “batches” of Parent data synced every 15 minutes?

Grateful for any assistance on this! Reliable, consistent DDA would make my forms much better.

Child.xlsx (9.3 KB)
Parent.xlsx (9.0 KB)

[Kal_Lam]

Welcome back to the community, @tomgr! Maybe try out the sample XLSForm shared in this support article to see if that works for you?

New Support Article: Dynamic Data Attachments [Case Management]

Dear All, We are glad to inform you that with the recent release of new feature Dynamic Data Attachments (Case management) in KoBoToolbox, we have added a new support article Dynamic Data Attachments to our support page. [image] Please visit our Help Center Page to learn more about other support articles. [image]

[tomgr]

Thank you @Kal_Lam. I used the documentation to build and deploy my forms, everything should be okay. Did you look at them? As simple as it gets, just to test out the feature before building more complex things.
I think the sample forms are a bit too much. They contain more stuff than needed to document the advertised feature: Other calculated fields, GPS coordinates, notes.

The only thing I can think of, is that the field is named Name in both Parent and Child. In the documentation the fields are prefixed with P_ and C_ respectively. But the docs also say, that " The parent project requires no additional modification from a normal XLSForm". So I don’t think that has anything to do with it. But can always test, of course.

And as I said, when the data is delivered to the forms, it works. The issue as I see it, is that it isn’t always parsed out from Parent to Child. And I haven’t found out what triggers the odd behavior. Any logging anywhere I can use?