在Python中實現多表關聯查詢通常使用SQLAlchemy庫來實現。SQLAlchemy是一個Python SQL工具包和對象關系映射（ORM）庫，可以幫助我們輕松地進行數據庫操作。

以下是一個簡單的示例，展示如何使用SQLAlchemy來實現多表關聯查詢：

首先，需要安裝SQLAlchemy庫：

pip install sqlalchemy

然后，我們可以按照以下步驟實現多表關聯查詢：

1. 導入必要的模塊：

from sqlalchemy import create_engine, Column, Integer, String, ForeignKey
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker, relationship

2. 創建數據庫連接和Session：

# 創建數據庫連接
engine = create_engine('sqlite:///database.db', echo=True)

# 創建Session
Session = sessionmaker(bind=engine)
session = Session()

3. 創建數據庫模型類：

Base = declarative_base()

class Department(Base):
    __tablename__ = 'departments'

    id = Column(Integer, primary_key=True)
    name = Column(String)

    employees = relationship('Employee', back_populates='department')

class Employee(Base):
    __tablename__ = 'employees'

    id = Column(Integer, primary_key=True)
    name = Column(String)
    department_id = Column(Integer, ForeignKey('departments.id'))

    department = relationship('Department', back_populates='employees')

4. 創建數據庫表：

Base.metadata.create_all(engine)

5. 插入數據：

engineering = Department(name='Engineering')
session.add(engineering)

session.add(Employee(name='John Doe', department=engineering))
session.add(Employee(name='Jane Smith', department=engineering))

session.commit()

6. 執行查詢：

employees = session.query(Employee).join(Department).filter(Department.name == 'Engineering').all()

for employee in employees:
    print(employee.name, employee.department.name)

通過以上步驟，可以實現多表關聯查詢，并輸出查詢結果。希望這個示例對你有所幫助。