from sqlalchemy import create_engine, Column, Integer, String, Float, ForeignKey, Table, Date
from sqlalchemy.orm import relationship
from model import Base

teacher_class = Table(
    "teacher_class",                        # 中间表的名字
    Base.metadata,                          # 绑定到 Base 的元数据
    Column("class_id", Integer, ForeignKey("classinfo.id"), primary_key=True),
    Column("teacher_id", Integer, ForeignKey("teacher.id"), primary_key=True) ,
    Column("role",String(50))

)