column value update based on stating columns input in data Entity

Hi All,

Need to update a column in data entity based on few columns of staging table.

created a new column (C1) in existing data entities using extension along with new columns ( S1,S2,S2) in staging table in extension.


-> Need to update column C1 based on values of S1,S2 and S3

Import format : excel ( Excel template has 3 columns S2,S2,S3 similar to Staging)

which event of staging or data entity has to override for above requirement?


Version: Dynamics AX 365 Operation (update 7)