Customer and Customer activity file

[tanaka ryouichi]

Hello.
I have a customer record and its associated customer activity records.
One customer has typically 1000 or 1500 activity records associated with.
Customer record also has last activity date to be updated whenever we have updated the activity file.

My question is everytime I read a customer record, activity files are read (just id). But I don't want to read activity record when I'm just updating customer record.

Also, when I'm inserting a new activity record to customer, I just want to add a activity record and don't want to read whole records.

How is everyone getting around this?

Thanks!