首先需要有python库sqlalchemy和psycopg2，如果没有的话可以在python.exe所在目录下打开命令行，输入：
pip install -i https://pypi.douban.com/simple sqlalchemy pip install -i https://pypi.douban.com/simple psycopg2接下来的连接语句如下：
from sqlalchemy import create_engine engine = create_engine('postgresql+psycopg2://user:password@hostname/database_name')其中user表示数据库的用户，password表示连接数据库的密码，hostname可以用localhost，databasee_name用你连接的数据库的名字，以下是一个示例：
import os from sqlalchemy import create_engine from sqlalchemy.orm import scoped_session, sessionmaker engine = create_engine('postgresql+psycopg2://postgres:88595073@localhost/lecture3') db = scoped_session(sessionmaker(bind=engine)) def main(): flights = db.execute("SELECT origin, destination, duration FROM flights").fetchall() for flight in flights: print(f"{flight.origin} to {flight.destination}, {flight.duration} minutes.") if __name__ == "__main__": main()
