Why is this Change Important & Necessary?

Closes #11247.

Grade overrides are used in two valid ways:

• for students who already submitted
• for students with no submission (for example makeup/external grading)

Previously, grading statistics could become confusing:

• completion could exceed 100%
• main grade card could appear incomplete/red due to no-submission overrides
• override visibility in stats was unclear
• in some cases, multiple no-submission overrides with equal marks could be undercounted in complete-stats count due to SQL deduplication behavior

This change makes completion and statistics behavior consistent and explicit.

What is the New Behavior?

1. TA completion percentage is bounded correctly.

• No-submission overrides no longer inflate TA completion beyond 100%.

2. Main gradeables page button/progress reflects submitted-work completion.

• No-submission overrides do not incorrectly force incomplete/red state.

3. Override split line is visible in non-peer stats view.

• Number of grade overrides: total (with submissions, without submissions)
• This line is shown even when override filter is off.
• When override filter is off, the UI now explicitly indicates that overrides are currently excluded from averages/counts.

4. Completely Graded Assignments count behavior is now correct with multiple overrides.

• Overrides for students with submissions replace those students’ base rows (no net count increase from those rows).
• Overrides for students without submissions add new rows.
• Query now uses UNION ALL for override rows, so multiple no-submission overrides with same marks are all counted.

5. Manual component statistics remain component-data based.

• Component averages/stddev/count do not change from total-score override entries (expected behavior).

What steps should a reviewer take to reproduce or test the bug or new feature?

Environment:

1. Use sample course in local/vagrant Submitty.
2. Use gradeable grades_released_homework (or equivalent non-team electronic gradeable).

Baseline:

1. Open grading status page.
   Link in case of Grades Released Homework grade card-
   http://localhost:1511/courses/s26/sample/gradeable/grades_released_homework/grading/status

Before moving forward, note that in top right corner there is a button edit filers, using this only you can modify what all various types of students will be included in statistics.
2. Note:

• Students who have submitted
• Current percentage of TA grading done
• Completely Graded Assignments count

Create override data:

1. Open Grade Override page for the same gradeable.
2. Add:

• at least 1 override for a student with submission
• at least 2 overrides for students without submission
• assign marks 10 to students so we can clearly observe change in mean values also
  To save you time, you can add override for these students and check-

Verify with Include Grade Overrides ON:

1. Open stats page, hard refresh.
2. Confirm:

• override split line reflects exact with/without counts
• completion percentage remains <= 100
• complete-stats count increases only by number of overridden students without submissions
  • Example pattern:
    • baseline = 98
    • overrides = 2 with submission + 2 without submission
    • expected complete count = 100

Verify with Include Grade Overrides OFF:

1. Uncheck Include Grade Overrides and apply.
2. Confirm:

• override split line still visible (informational)
• text indicates overrides are excluded from averages/counts
• complete-stats count returns to baseline override-excluded value

Main page verification:

1. Go to course gradeables page.
2. Confirm target gradeable grading card is not incorrectly red due solely to no-submission overrides.

Automated Testing & Documentation

Automated testing:

1. Updated Cypress TAGrading stats coverage for completion guard under filter toggles.
2. Ran override feature spec successfully.
3. Existing unrelated instability remains in one TAGrading afterEach path (pre-existing); core behavior validated manually end-to-end for this fix.

Documentation:

• No submitty.org update required for this bugfix.
• Can open follow-up docs issue if maintainers want explicit override-count semantics documented.

Other information

1. Breaking change: No
2. Migration required: No
3. Security concerns: None identified