fix: analysis

backend/app/services/assessment_service.py

@@ -3,7 +3,7 @@ import logging
 from uuid import UUID
 
 import httpx
-from sqlalchemy import select
+from sqlalchemy import delete, select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.core.config import settings
@@ -15,7 +15,14 @@ logger = logging.getLogger(__name__)
 
 
 async def assess_case(case_id: UUID, db: AsyncSession) -> list[FraudAssessment]:
-    """Run rule-based assessment on all non-duplicate transactions and generate reasons."""
+    """Run rule-based assessment on all non-duplicate transactions and replace old results."""
+    # Replace mode: rerun analysis for the same case should overwrite prior assessments
+    # instead of appending duplicated rows.
+    await db.execute(
+        delete(FraudAssessment).where(FraudAssessment.case_id == case_id)
+    )
+    await db.flush()
+
     result = await db.execute(
         select(TransactionRecord)
         .where(TransactionRecord.case_id == case_id)