#!/usr/bin/env python
# -*- coding:utf-8 -*-
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String, ForeignKey, UniqueConstraint, Index
from sqlalchemy.orm import sessionmaker, relationship
from sqlalchemy import create_engine
engine = create_engine("mysql+pymysql://root@127.0.0.1:3306/sig") #engine 引擎
Base = declarative_base() #declarative 声明的 base 基地
# 创建单表
class Users(Base):
__tablename__ = 'users' #表名
id = Column(Integer, primary_key=True)
name = Column(String(32))
extra = Column(String(16))
num = Column(Integer)
#args 传感器
__table_args__ = (
UniqueConstraint('id', 'name', name='uix_id_name'), #Constraint 约束 unique 唯一
Index('ix_id_name', 'name', 'extra'),
)
def __repr__(self):
return "%s-%s-%s_%s" %(self.id, self.name,self.extra,self.num)
# 创建一对多
class Favor(Base):
__tablename__ = 'favor'
nid = Column(Integer, primary_key=True)
caption = Column(String(50), default='red', unique=True)
def __repr__(self):
return "%s-%s" %(self.nid, self.caption)
class Person(Base):
__tablename__ = 'person'
nid = Column(Integer, primary_key=True)
name = Column(String(32), index=True, nullable=True)
favor_id = Column(Integer, ForeignKey("favor.nid"))
def __repr__(self):
return "%s-%s-%s" %(self.nid, self.name,self.favor_id)
# 创建多对多
class Group(Base):
__tablename__ = 'group'
id = Column(Integer, primary_key=True)
name = Column(String(64), unique=True, nullable=False)
port = Column(Integer, default=22)
class Server(Base):
__tablename__ = 'server'
id = Column(Integer, primary_key=True, autoincrement=True)
hostname = Column(String(64), unique=True, nullable=False)
class ServerToGroup(Base):
__tablename__ = 'servertogroup'
nid = Column(Integer, primary_key=True, autoincrement=True)
server_id = Column(Integer, ForeignKey('server.id'))
group_id = Column(Integer, ForeignKey('group.id'))
Base.metadata.create_all(engine) #metadata元数据 把创建的表格发送給数据库
Session = sessionmaker(bind=engine) #session 会话 maker制造者 sessionmaker会话者
session = Session() #创建一个session对象
# 写入数据
# obj = Users(name="alex0", extra='sb')
# session.add(obj)
# session.add_all([
# Users(name="alex1", extra='sb'),
# Users(name="alex2", extra='sb'),
# ])
#删除数据
# session.query(Users).filter(Users.id > 2).delete() #query查询 filter过滤
# session.commit()
# 改数据
# session.query(Users).filter(Users.id < 3).update({"name" : "alxe" })
# session.query(Users).filter(Users.id < 3).update({Users.name: Users.name + "199"}, synchronize_session=False) #synchronize使用同步
# session.query(Users).filter(Users.id < 3).update({"num": Users.num + 1}, synchronize_session="evaluate") #evaluate评价 估价 求的值
# session.commit()
# 查看数据
# ret = session.query(Users).all()
# ret = session.query(Users.name, Users.extra).all()
# ret = session.query(Users).filter_by(name='alxe199').all()
# ret = session.query(Users).filter_by(name='alxe199').first()
# 条件
# ret = session.query(Users).filter_by(name='alxe199').all()
# ret = session.query(Users).filter(Users.id > 1, Users.name == 'eric').all()
# ret = session.query(Users).filter(Users.id.between(1, 3), Users.name == 'eric').all() #between 在什么 之间
# ret = session.query(Users).filter(Users.id.in_([1,3,4])).all()
# ret = session.query(Users.id).filter_by(name='eric').all()
# ret = session.query(Users).filter(Users.id.in_(session.query(Users.id).filter_by(name='eric'))).all()
# from sqlalchemy import and_, or_ #模块 and并且 or或者
# ret = session.query(Users).filter(and_(Users.id > 2, Users.name == 'eric')).all()
# # ret = session.query(Users).filter(or_(Users.id < 4, Users.name == 'eric')).all()
# ret = session.query(Users).filter(
# or_(
# Users.id < 2,
# and_(Users.name == 'eric', Users.id > 3),
# Users.extra != ""
# )).all()
# 通配符
# ret = session.query(Users).filter(Users.name.like('e%')).all()
# ret = session.query(Users).filter(~Users.name.like('e%')).all() # ~ 符号是相反的意思, 除了这个条件 其他都成立
# 限制
# ret = session.query(Users)[1:5] #取 1-5
# 排序
# ret = session.query(Users).order_by(Users.id.desc()).all()
# ret = session.query(Users).order_by(Users.name.desc(), Users.id.asc()).all()
# 分组
from sqlalchemy.sql import func
# ret = session.query(Users).group_by(Users.name).all()
# ret = session.query(
# func.max(Users.id),
# func.sum(Users.id),
# func.min(Users.id)).group_by(Users.name).all()
# ret = session.query(
# func.max(Users.id),
# func.sum(Users.id),
# func.min(Users.id)).group_by(Users.name).having(func.min(Users.id) >2).all()
# 连表
# ret = session.query(Users, Favor).filter(Users.id == Favor.nid).all()
# ret = session.query(Person).join(Favor).all()
# ret = session.query(Person,Favor).join(Favor).all()
# ret = session.query(Person.name('aaa'),Favor.('caption')).join(Favor).all() # 添加一个别名
#
# ret = session.query(Person).join(Favor, isouter=True).all()
# 组合
# q1 = session.query(Users.name).filter(Users.id > 2)
# q2 = session.query(Favor.caption).filter(Favor.nid < 2)
# ret = q1.union(q2).all()
# q1 = session.query(Users.name).filter(Users.id > 2)
# q2 = session.query(Favor.caption).filter(Favor.nid < 2)
# ret = q1.union_all(q2).all()
# print(ret)
session.commit() #commit 把。。。托付給 把写入的内容发送給数据库