Offline MDK data synchronisation error

[Girish_KR]

H,

I am getting the below error in MDK application, while trying to initialise ODATA local storage.

Error: [-10340] The download failed due to an error on the server: -857 (SERVER_SYNCHRONIZATION_ERROR) ([-10225] Message: User exception: [-100000] An unexpected error occurred while converting the OData metadata to the Offline OData client database metadata: An exception occurred.

Error caused by: An exception occurred.) : Error: [-10340] The download failed due to an error on the server: -857 (SERVER_SYNCHRONIZATION_ERROR) ([-10225] Message: User exception: [-100000] An unexpected error occurred while converting the OData metadata to the Offline OData client database metadata: An exception occurred. Error caused by: An exception occurred.)

Regards,

Girish

[Girish_KR · Accepted solution]

metadata.xmlThis was mainly a metadata issue.
We had a metadata with two schemas like:
<?xml version='1.0' encoding='UTF-8'?>

<edmx:Edmx xmlns:edmx="http://schemas.microsoft.com/ado/2007/06/edmx" Version="1.0"> <edmx:DataServices m:DataServiceVersion="1.0" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata"> <Schema Namespace="com.app.demo.entity" xmlns="http://schemas.microsoft.com/ado/2008/09/edm"> </Schema> <Schema Namespace="com.app.demo.edm" xmlns="http://schemas.microsoft.com/ado/2008/09/edm"> </Schema> </edmx:DataServices></edmx:Edmx>
</xml>

Later we combined the two into a single schema

<edmx:Edmx xmlns:edmx="http://schemas.microsoft.com/ado/2007/06/edmx" Version="1.0"> <edmx:DataServices m:DataServiceVersion="1.0" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata"> <Schema Namespace="com.app.demo.entity" xmlns="http://schemas.microsoft.com/ado/2008/09/edm"> </Schema> </edmx:DataServices></edmx:Edmx>
</xml>
Let me know if this helps.

[sopizaken · Accepted solution]

Hi Girish,

Thank you for your inputs. I have checked our metadata structure and saw that we only have one schema. I think our problem is about the bulk of data that we are retrieving on initial load. I have already set a "top" filter in my list on initial load of the app, but it seems like it still gets all the data. Do you have any idea how to limit the data pull from the backend on initial load of the mdk project on a device?

[Girish_KR]

Hi Rachel,
Could you please elaborate on how you are able to download all data? I am facing some issues achieving it.

[sopizaken]

Hi Girish,

I am not able to download all data as i am encountering the SERVER_SYNCHRONIZATION_ERROR.

I tried to add a "$top=10" query option on InitializeOffline.action, but would always display a single item even if there are thousands of records. But when i try to fetch specific items, they are correctly retrieved. Would you know how to fix this issue?

[bill_froelich]

This sounds like a different issue that happens to be resulting in the same error originally reported. I would recommend opening a new question to better track the issue.

[Girish_KR]

Yes Rachel, the issue is resolved now.

[sopizaken]

Could you share the solution you have made to fix the issue?

[sopizaken]

Hi girish.kumar123 ,

Were you able to fix the issue? We are currently having the same issues.

[guo-pingzhang]

Are you using NEO or CF? NEO only support Odata V2. CF supports both V2 and V4.

You could take a look at event log on CF and server log+event log on NEO. There might be more info like stacktrace.

Can you capture a networktrace or attach your backend $metadata. It might be useful to take a look at metadata.

Thanks, Guoping