The data source is not embedded within a (parent) data source.
Write COC for FORM DS extension method
(In my case, SalesTable (Form) & SalesLine_IN (DS)). Even IN region localization not enabled.
Note: This has been fixed by MS as part of PU43 (10.0.19) + QU
1. Code fix solution (Temporary)
// Temporary fix for "The data source is not embedded within a (parent) data source." Error while opening All Sales order form after upgrade PU43 (10.0.19)
void init()
{
next init();
this.insertIfEmpty(false);
this.allowCreate(false);
}
2. Workaround solution (Temporary)
//Changed personalize view to Standard view