v2.6更新

backend/models/subject.py

@@ -71,18 +71,18 @@ class SubjectModel:
     
     @staticmethod
     async def has_related_data(subject_id: int) -> bool:
-        """检查科目是否有关联数据"""
-        return False
+        """检查科目是否有关联的作业数据"""
+        sql = "SELECT COUNT(*) AS cnt FROM assignments WHERE subject_id = %s"
+        result = await execute_one(sql, (subject_id,))
+        return result and result.get("cnt", 0) > 0
     
     @staticmethod
     async def delete(subject_id: int) -> bool:
-        """软删除科目（设置 is_active = 0），如果已禁用也返回成功"""
+        """真正删除科目记录"""
         subject = await SubjectModel.get_by_id(subject_id)
         if not subject:
             return False
-        if subject.get("is_active") == 0:
-            return True  # 已禁用，视为成功
-        sql = "UPDATE subjects SET is_active = 0 WHERE subject_id = %s"
+        sql = "DELETE FROM subjects WHERE subject_id = %s"
         result = await execute_update(sql, (subject_id,))
         return result > 0