from sqlalchemy import Column, String, create_engine, Integer, Text
from sqlalchemy.orm import sessionmaker
from sqlalchemy.ext.declarative import declarative_base
import time
# 创建对象的基类:
Base = declarative_base()
# 定义User对象:
class User(Base):
# 表的名字:
__tablename__ = 'users'
# 表的结构:
id = Column(Integer, autoincrement=True, primary_key=True, unique=True, nullable=False)
name = Column(String(50), nullable=False)
sex = Column(String(4), nullable=False)
nation = Column(String(20), nullable=False)
birth = Column(String(8), nullable=False)
id_address = Column(Text, nullable=False)
id_number = Column(String(18), nullable=False)
creater = Column(String(32))
create_time = Column(String(20), nullable=False)
updater = Column(String(32))
update_time = Column(String(20), nullable=False, default=time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()),
onupdate=time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
comment = Column(String(200))
# 初始化数据库连接:
engine = create_engine('postgres://postgres:123123@localhost:5432/postgres') # 用户名:密码@localhost:端口/数据库名
# 创建DBSession类型:
DBSession = sessionmaker(bind=engine)
def createTable():
# 创建表
Base.metadata.create_all(engine)
def insertData():
# 插入操作
# 创建会话
session = DBSession()
# 创建新User对象:
local_time = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime())
new_user = User(name='hsh4', sex='男', nation='汉', birth='19991012', id_address='广州大学', id_number='441242142142',
create_time=local_time)
# 添加到session:
session.add(new_user)
# 提交即保存到数据库:
session.commit()
# 关闭session:
session.close()
def selectData():
# 查询操作
# 创建Session
session = DBSession()
# 创建Query查询,filter是where条件,最后调用one()返回唯一行,如果调用all()则返回所有行:
user = session.query(User).filter(User.id == '1' and User.name == 'hsh4').one()
print('name:', user.name)
print('id_address:', user.id_address)
session.close() # 关闭Session
def updateData():
# 更新操作
session = DBSession() # 创建会话
users = session.query(User).filter_by(name="hsh4").first() # 查询条件
users.id_number = "abcd" # 更新操作
session.add(users) # 添加到会话
session.commit() # 提交即保存到数据库
session.close() # 关闭会话
def deleteData():
# 删除操作
session = DBSession() # 创建会话
delete_users = session.query(User).filter(User.id == "1").first()
if delete_users:
session.delete(delete_users)
session.commit()
session.close() # 关闭会话
def dropTable():
# 删除表
session = DBSession() # 创建会话
session.execute('drop table users')
session.commit()
session.close()
# createTable()
# insertData()
# selectData()
# updateData()
# deleteData()