The distinction between Foreground access and Background access applies to both queries (SELECT, in SQL terms) and data manipulation (INSERT, UPDATE, DELETE, in SQL terms).
Background access consists of only the following 2 types of indirect access:
•Access by a constraint, as an indirect result of a user action;
•Access by a corrective relationship attribute setting as an indirect result of a user action. Corrective relationship attributes are Delete Rule and Update Rule settings other than Restricted (ie., Cascading or Nullify).
Foreground access consists of all other types of access to data, for example:
•Access through (fields in) info windows and web forms based on the table or column.
•Access to tables and columns by calling USoft Batch jobs that access the table or column.
•Access to tables and columns by calling USoft REST service methods that access the table or column.