day40--mysql step4 SQLAlchemy

1、unique = True 表示启动唯一索

2、有add 必须有commit这样数据才会提交

3、ORM功能

#!/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:123@127.0.0.1:3306/t1", max_overflow=5)

Base = declarative_base()

# 创建单表

class Users(Base):

    __tablename__ = 'users'

    id = Column(Integer, primary_key=True)

    name = Column(String(32))

    extra = Column(String(16))

    __table_args__ = (

    UniqueConstraint('id', 'name', name='uix_id_name'),

        Index('ix_id_name', 'name', 'extra'),

    )

# 一对多

class Favor(Base):

    __tablename__ = 'favor'

    nid = Column(Integer, primary_key=True)

    caption = Column(String(50), default='red', unique=True)

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"))

# 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'))

def init_db():

    Base.metadata.create_all(engine)

def drop_db():

    Base.metadata.drop_all(engine)

建表

#!/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:123@127.0.0.1:3306/t1", max_overflow=5)

Base = declarative_base()

# 创建单表

class Users(Base):

    __tablename__ = 'users'

    id = Column(Integer, primary_key=True)

    name = Column(String(32))

    extra = Column(String(16))

    __table_args__ = (

    UniqueConstraint('id', 'name', name='uix_id_name'),

        Index('ix_id_name', 'name', 'extra'),

    )

    def __repr__(self):

        return "%s-%s" %(self.id, self.name)

# 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"))

    # 与生成表结构无关，仅用于查询方便

    favor = relationship("Favor", backref='pers')

# 多对多

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'))

    group = relationship("Group", backref='s2g')

    server = relationship("Server", backref='s2g')

class Group(Base):

    __tablename__ = 'group'

    id = Column(Integer, primary_key=True)

    name = Column(String(64), unique=True, nullable=False)

    port = Column(Integer, default=22)

    # group = relationship('Group',secondary=ServerToGroup,backref='host_list')

class Server(Base):

    __tablename__ = 'server'

    id = Column(Integer, primary_key=True, autoincrement=True)

    hostname = Column(String(64), unique=True, nullable=False)

def init_db():

    Base.metadata.create_all(engine)

def drop_db():

    Base.metadata.drop_all(engine)

Session = sessionmaker(bind=engine)

session = Session()

表结构 + 数据库连接

连接db

#增

obj = Users(name="alex0", extra='sb')

session.add(obj)

session.add_all([

    Users(name="alex1", extra='sb'),

    Users(name="alex2", extra='sb'),

])

session.commit()

#删

session.query(Users).filter(Users.id > 2).delete()

session.commit()

#改

session.query(Users).filter(Users.id > 2).update({"name" : ""})

session.query(Users).filter(Users.id > 2).update({Users.name: Users.name + ""}, synchronize_session=False)

session.query(Users).filter(Users.id > 2).update({"num": Users.num + 1}, synchronize_session="evaluate")

session.commit()

#查

ret = session.query(Users).all()

ret = session.query(Users.name, Users.extra).all()

ret = session.query(Users).filter_by(name='alex').all()

ret = session.query(Users).filter_by(name='alex').first()

ret = session.query(Users).filter(text("id<:value and name=:name")).params(value=224, name='fred').order_by(User.id).all()

ret = session.query(Users).from_statement(text("SELECT * FROM users where name=:name")).params(name='ed').all()

#其他

#　条件

ret = session.query(Users).filter_by(name='alex').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()

ret = session.query(Users).filter(Users.id.in_([1,3,4])).all()

ret = session.query(Users).filter(~Users.id.in_([1,3,4])).all()

ret = session.query(Users).filter(Users.id.in_(session.query(Users.id).filter_by(name='eric'))).all()

from sqlalchemy import and_, or_

ret = session.query(Users).filter(and_(Users.id > 3, Users.name == 'eric')).all()

ret = session.query(Users).filter(or_(Users.id < 2, 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()

# 限制

ret = session.query(Users)[1:2]

# 排序

ret = session.query(Users).order_by(Users.name.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.extra).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).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()

数据库操作

条件用 filter单值用filter_by

4、示例代码

#!/usr/bin/env python

# -*- coding:utf-8 -*-

#coding:utf8

import sqlalchemy

from sqlalchemy import create_engine

from sqlalchemy.ext.declarative import declarative_base

from sqlalchemy import Column, Integer, String

from sqlalchemy.orm import sessionmaker

print(sqlalchemy.__version__)

engine = create_engine('mysql+pymysql://sysadmin:password01!@10.10.8.12:3306/q2')

Base = declarative_base()#生成一个SQLORM基类

class User(Base):

    __tablename__ = 'sqlalchemydemo'

    id = Column(Integer, primary_key=True, autoincrement=True)

    name = Column(String(40))

    fullname = Column(String(40))

    password = Column(String(40))

    def __repr__(self):

       return "<User(name='%s', fullname='%s', password='%s')>" % (

                            self.name, self.fullname, self.password)

Base.metadata.create_all(engine)  #创建所有表结构

# Base.metadata.drop_all(engine)  # 删除所有表

# ed_user = User(name='xiaoyu', fullname='Xiaoyu Liu', password='123')

# print(ed_user)

# #这两行触发sessionmaker类下的__call__方法，return得到 Session实例，赋给变量session，所以session可以调用Session类下的add，add_all等方法

MySession = sessionmaker(bind=engine)

session = MySession()

# session.add(ed_user)    ##添加数据

# our_user = session.query(User).filter_by(name='ed').first()

# SELECT * FROM users WHERE name="ed" LIMIT 1;

# session.add_all([

#     User(name='alex', fullname='Alex Li', password='456'),

#     User(name='alex', fullname='Alex old', password='789'),

#     User(name='peiqi', fullname='Peiqi Wu', password='sxsxsx')])

#

# session.commit()

#print(">>>",session.query(User).filter_by(name='ed').first())

# print(session.query(User).all())  #表内容

# for row in session.query(User).order_by(User.id):

#      print(row)

# for row in session.query(User).filter(User.name.in_(['alex', 'wendy', 'jack'])):＃这里的名字是完全匹配

#     print(row)

# for row in session.query(User).filter(~User.name.in_(['ed', 'wendy', 'jack'])):

#     print(row)

# print(session.query(User).filter(User.name == 'ed').count())

from sqlalchemy import and_, or_

# for row in session.query(User).filter(and_(User.name == 'ed', User.fullname == 'Ed Jones')):

#     print(row)

for row in session.query(User).filter(or_(User.name == 'ed', User.fullname == 'wendy')):

    print(row)

lone

#!/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://sysadmin:password01!@10.10.8.12:3306/q2')

Base = declarative_base()

class Son(Base):

    __tablename__ = 'son'

    id = Column(Integer, primary_key=True)

    name = Column(String(32))

    age = Column(String(16))

    father_id = Column(Integer, ForeignKey('father.id'))

    # father = relationship('Father')

    # __table_args__ = (

    #     UniqueConstraint('id', 'name', name='uix_id_name'),

    #     Index('ix_id_name', 'name', 'extra'),

    # )

    #

class Father(Base):

    __tablename__ = 'father'

    id = Column(Integer, primary_key=True)

    name = Column(String(32))

    age = Column(String(16))

    son = relationship('Son', backref = 'father')

Base.metadata.create_all(engine)

Session = sessionmaker(bind=engine)

session = Session()

# ret3 = session.query(Father).filter_by(id=1).all()

# ret4 = session.query(Father).filter_by(id=4).first()

# for ii in ret4.son:

#     print(ii.name)

# s1 = session.query(Son).filter_by(id=1).first()

# print(s1.father.name,s1.name)

ret4 = session.query(Father).filter_by(id=4).first()

w4 = Son(name = 'little alvin4',age = 5)

ret4.son.append(w4)

session.add(ret4)

session.commit()

# print(ret3)

# for i in ret3:

#     print(i.name)

#

# ret1 = session.query(Father.name.label('kkk'), Son.name.label('ppp')).join(Son)

#

# ret = session.query(Father.name.label('kkk'), Son.name.label('ppp')).join(Son).all()

# print(ret1)

# print(ret)

#

# print(len(ret))

# for ii in ret:

#     print(ii)

# # f1 = Father(name='alvin4', age=50)

# w1 = Son(name='little alvin1', age=4, father_id = 2)

# w2 = Son(name='little alvin2', age=5, father_id = 2)

# #

# # f1.son = [w1, w2]

# # session.add(f1)

#

# session.add_all([w1,w2])

# session.commit()

one2many

#!/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://sysadmin:password01!@10.10.8.12:3306/q2?charset=utf8')

Base = declarative_base()

class Men_to_Wemon1(Base):

    __tablename__ = 'men_to_wemon1'

    nid = Column(Integer, primary_key=True)

    men_id = Column(Integer, ForeignKey('men1.id'))

    women_id = Column(Integer, ForeignKey('women1.id'))

class Men1(Base):

    __tablename__ = 'men1'

    id = Column(Integer, primary_key=True)

    name = Column(String(32))

    age= Column(String(16))

class Women1(Base):

    __tablename__ ='women1'

    id = Column(Integer, primary_key=True)

    name = Column(String(32))

    age= Column(String(16))

    bf=relationship("Men1",secondary=Men_to_Wemon1.__table__,backref='gf')

Base.metadata.create_all(engine)

#

Session = sessionmaker(bind=engine)

session = Session()

#

# m1=Men1(name='alex',age=18)

# m2=Men1(name='wusir',age=18)

# w1=Women1(name='如花',age=40)

# w2=Women1(name='铁锤',age=45)

# t1 = Men_to_Wemon1(men_id=1,women_id=2)

m1 = session.query(Men1).filter_by(id = 2).first()

w1 = session.query(Women1).all()

m1.gf=w1

# m1.gf=[w1,w2]

# w1.bf=[m1,m2]

session.add_all([m1,])

# session.add_all([m1,m2,w1,w2])

# session.add(t1)

session.commit()

many2many

#!/usr/bin/env python

# -*- coding:utf-8 -*-

from sqlalchemy import create_engine, and_, or_, func, Table

from sqlalchemy.ext.declarative import declarative_base

from sqlalchemy import Column, Integer, String, ForeignKey

from  sqlalchemy.orm import sessionmaker, relationship

engine = create_engine('mysql+pymysql://sysadmin:password01!@10.10.8.12:3306/q2?charset=utf8')

Base = declarative_base()  # 生成一个SqlORM 基类

class HostToGroup(Base):

    __tablename__ = 'host_2_group'

    nid = Column(Integer, primary_key=True)

    host_id = Column(Integer, ForeignKey("host.id"))

    group_id = Column(Integer, ForeignKey("group.id"))

class Host(Base):

    __tablename__ = 'host'

    id = Column(Integer, primary_key=True, autoincrement=True)

    hostname = Column(String(64), unique=True, nullable=False)

    ip_addr = Column(String(128), unique=True, nullable=False)

    port = Column(Integer, default=22)

    group = relationship('Group',

                         secondary=HostToGroup.__table__,

                         backref='host_list')

    # group =relationship("Group",back_populates='host_list')

    def __repr__(self):

        return "<id=%s,hostname=%s, ip_addr=%s>" % (self.id,

                                                    self.hostname,

                                                    self.ip_addr)

class Group(Base):

    __tablename__ = 'group'

    id = Column(Integer, primary_key=True)

    name = Column(String(64), unique=True, nullable=False)

    def __repr__(self):

        return "<id=%s,name=%s>" % (self.id, self.name)

Base.metadata.create_all(engine)  # 创建所有表结构

if __name__ == '__main__':

    SessionCls = sessionmaker(bind=engine)

    session = SessionCls()

    #

    # g1 = Group(name='g1')

    # g2 = Group(name='g2')

    # g3 = Group(name='g3')

    # g4 = Group(name='g4')

    # session.add_all([g1,g2,g3,g4])

    # h1 = Host(hostname='h1',ip_addr='192.168.1.56')

    # h2 = Host(hostname='h2',ip_addr='192.168.1.57',port=10000)

    # h3 = Host(hostname='ubuntu',ip_addr='192.168.1.58',port=10000)

    #

    # h1.group=[g2,g4]

    # session.add_all([h1,h2,h3])

    # session.commit()

    # groups = session.query(Group).all()

    # h2 = session.query(Host).filter(Host.hostname=='h2').first()

    # h2.group = groups[:-1]

    # print("===========>",h2.group)

    g4 = session.query(Group).filter(Group.name=='g4').first()

    print(g4)

    obj1 = session.query(Host).filter(Host.hostname=='h1').update({'port':444})

    obj2 = session.query(Host).filter(Host.hostname=='h1').first()

    # g4.host_list.append(obj2)

    obj2.group.append(g4)

    #

    # obj2= session.query(Host).filter(Host.hostname=='h1').first()

    # print("h1:",obj2.group)

    # print("g:",g4.host_list )

    session.commit()

many2many2

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