(7)-d. Save relational object data

If you save a page in the editing screen, only the record information modified are updated in a data table or in a multiple-row data table, except for a "read-only table".
Please refer to the below if you are using a workflow rule or Apex Trigger. (Up until V3.1, all record information was subject to be updated).

 

Until V3.1

V3.2

Parent Data

A record was updated when clicking the save button. Workflow rules or Apex Triggers used to be applied.

Same as left

Child Data

If you click the save button, all records were updated and workflow rules and Apex Triggers were activated.

If you click the save button, only the records you changed are updated. Workflow rules and Apex Triggers are activated only for the changed records.