Exclude null compatibility scores when ordering profiles by compatibility. Update compute-scores logic to delete invalid score rows instead of setting them to null. Add corresponding test coverage.

backend/api/src/get-profiles.ts

@@ -659,6 +659,10 @@ export const loadProfiles = async (props: profileQueryType, db?: SupabaseDirectC
                     : '90 days',
       }),
 
+    // Precomputed scores can be nulled out (e.g. after the user deletes their last shared
+    // prompt) instead of the row being removed — don't surface those as matches.
+    orderByParam === 'compatibility_score' && where('cs.score IS NOT NULL'),
+
     // Exclude profiles that the requester has chosen to hide
     userId &&
       where(

backend/api/tests/unit/get-profiles.unit.test.ts

@@ -319,4 +319,20 @@ describe('loadProfiles', () => {
       expect(profilesModule.loadProfiles(props)).rejects.toThrowError('Incompatible with user ID')
     })
   })
+
+  describe('when ordering by compatibility score', () => {
+    it('excludes profiles whose precomputed score was nulled out', async () => {
+      ;(mockPg.map as jest.Mock).mockResolvedValue([])
+      ;(mockPg.one as jest.Mock).mockResolvedValue(0)
+
+      await profilesModule.loadProfiles({
+        orderBy: 'compatibility_score',
+        compatibleWithUserId: 'user-1',
+      })
+
+      const [query] = mockPg.map.mock.calls[0]
+
+      expect(query).toContain('cs.score IS NOT NULL')
+    })
+  })
 })

backend/shared/src/compatibility/compute-scores.ts

@@ -29,11 +29,12 @@ export async function recomputeCompatibilityScoresForUser(
   // Load all answers for the target user
   const answersSelf = await getAnswersForUser(userId)
 
-  // If the user has no answered questions, set the score to null
+  // If the user has no answered questions, there's no valid score to keep for any pair
+  // involving them — remove the rows rather than nulling them out, so a row's existence
+  // always means "we have a valid score for this pair".
   if (!hasAnsweredQuestions(answersSelf)) {
     await pg.none(
-      `update compatibility_scores
-       set score = null
+      `delete from compatibility_scores
        where user_id_1 = $1
           or user_id_2 = $1`,
       [userId],