Ignore blank field in Data Extension import file activity

Question

I am using Automations and an Import File Activity to ingest events logs in a specific data extension.

Salesforce is reading a log of successive events, so I am leaving blank field in my CSV log to be completed afterward. For instance, here is the type of .CSV file I am able to create:

event_id;subevent_1_date;subevent_2_date;some_boolean_data
123;2019-07-03;;true
123;;2019-07-04;true

And I want my Salesforce Marketing Cloud Data Extension to look like (the event_id is my primary key):

event_id;subevent_1_date;subevent_2_date;some_boolean_data
123;2019-07-03;2019-07-04;true

The issue here is that using the Update option in the Import File activity, Salesforce will only keep the last version of the event, as if I could replay every field instead of giving them one after another. So the result would be:

event_id;subevent_1_date;subevent_2_date;some_boolean_data
123;;2019-07-04;true

I am wondering whereas it is possible for the Import file Activity to ignore blank field so I can successively update different field in my Data Extension. Is there a way of doing that ?

Thanks!

Answer 1

You should think about your structure once again.
It would make more sense to have a data extension with:

event_id;subevent_id;subevent_date;some_boolean_data

Then the primary key would stretch over event_id and subevent_id. Therefore each subevent has its own row and you can run SQL Queries if you are set on your data extension design to get to that look.