Implement primary key-only count for other endpoints

[lbeaufort]

What we're after:
Adding primary key only counts improves performance. We only have this in place currently for schedule a, so we should add it to our other large endpoints.

No locust test needed.
Look at this issue from when we did it before: #4368

Completion criteria:

• Implement primary key only count in schedule b and e. (We will wait for others that don't have primary key)