Context:

In a recent support ticket we discovered that it is possible for old engine process instance data to not have a definitionKey set. In Optimize 3.4, we introduce instance indices which depend on the definitionKey to be present in instance data. Due to this, customers may observe NPEs during import.

This can either be resolved by enriching the old instance data with the missing definitionkey or by upgrading to Optimize 3.5 where this issue will be fixed (with OPT-5220).

This should be documented as a know issue in the 3.3 -> 3.4 migration notes.

AT:

• The migration notes document the above issue along with how to resolve it (adjusting engine data or upgrading to 3.5)