diff --git a/model/dao/score_dao.py b/model/dao/score_dao.py
new file mode 100644
index 0000000..09510ab
--- /dev/null
+++ b/model/dao/score_dao.py
@@ -0,0 +1,116 @@
+# dao/score_dao.py
+from sqlalchemy.orm import Session
+from model.score import Score
+from model.student import Student
+
+
+ # 查
+
+# 查一个学生所有成绩
+
+def get_score(db: Session, student_id: int):
+    return db.query(Score).filter(
+        Score.student_id == student_id,
+        Score.is_deleted == 0,
+    ).order_by(Score.exam_seq.asc()).all()
+
+
+
+# 查某学生的某次成绩
+def get_one_score(db: Session, student_id: int, exam_seq: int):
+
+    return db.query(Score).filter(
+        Score.student_id == student_id,
+        Score.exam_seq == exam_seq,
+        Score.is_deleted == 0,
+    ).first()
+
+
+
+# 查不及格的
+def get_warning(db: Session):
+    return db.query(Score).filter(
+        Score.is_warning == 1,
+        Score.is_deleted == 0,
+    ).all()
+
+
+
+
+
+
+# 录
+
+
+# 录信息
+def add_score(db: Session, student_id: int, exam_seq: int, score: float):
+
+    stu = db.query(Student).filter(Student.id == student_id).first()
+    if not stu:
+        return None, "学生不存在"
+
+
+    exists = get_one_score(db, student_id, exam_seq)
+    if exists:
+        return None, "该学生这次成绩已录过"
+
+
+
+    new_score = Score(
+        student_id=student_id,
+        exam_seq=exam_seq,
+        score=score,
+        is_warning=1 if score < 60 else 0,
+        is_deleted=0,
+    )
+    db.add(new_score)
+    db.commit()
+    db.refresh(new_score)
+    return new_score, None
+
+
+
+
+
+#  改
+
+  # 改成绩
+
+def update_score(db: Session, student_id: int, exam_seq: int, new_score: float):
+
+
+    obj = get_one_score(db, student_id, exam_seq)
+    if not obj:
+        return None, "成绩不存在或已删除"
+
+    obj.score = new_score
+
+    # 如果不及格 预警重置
+    obj.is_warning = 1 if new_score < 60 else 0
+
+    db.commit()
+    db.refresh(obj)
+    return obj, None
+
+
+
+
+
+# 逻辑删除
+
+
+def delete_score(db: Session, student_id: int, exam_seq: int):
+  # 把删除的学生0改成1
+
+    obj = get_one_score(db, student_id, exam_seq)
+
+    if not obj:
+        return None, "成绩不存在或已删除"
+
+
+  # 0 → 1
+    obj.is_deleted = 1
+    db.commit()
+    return obj, None
+
+