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Python-資料庫-mysql-sqlalchemy

Python
資料庫
mysql-sqlalchemy

安裝
Linux、mac : pip3 install SQLAlchemy
windows     :之後補充

第一部分
from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker

engine = create_engine('sqlite:///:memory', echo=False)
Base = declarative_base()
Session = sessionmaker(bind=engine)


第二部分
from test_sqlalchemy import *
from sqlalchemy import Column, Integer, String

class User(Base):
__tablename__ = 'users'
id = Column(Integer, primary_key=True)
name = Column(String)
fullname = Column(String)
password = Column(String)

def __repr(self):
return "<User(name={})>".format(self.name)


第三部分
from test_sqlalchemy import *
from build_model import *

Base.metadata.create_all(engine)
user1 = User(name='user1', fullname='user1', password='user1')
user2 = User(name='user2', fullname='user2', password='user2')
user3 = User(name='user3', fullname='user3', password='user3')

# Insert Data
session = Session()
session.add(user1)
session.add(user2)
session.add(user3)
session.commit()
print('------------------')
# Search Data
for name,fullname in session.query(User.name,User.fullname):
print(name, fullname)
print('------------------')
# Modify Data
user1.fullname = 'user1 fullname version'
session.commit()
for name,fullname in session.query(User.name,User.fullname):
print(name, fullname)
print('------------------')
# Delete Data
session.delete(user1)
session.delete(user2)
session.delete(user3)
session.commit()
for name,fullname in session.query(User.name,User.fullname):
print(name, fullname)

print('------------------')


session.close()

程式碼說明

第一部分:定義engine,這邊使用sqlite,定義base模型,定義session
第二部分:定義model類別,繼承自base
第三部分:
執行階段,建立資料庫,建立使用者資料,加入session,並執行,
搜尋資料
修正資料,並執行
刪除資料,並執行,顯示刪除後資料庫

留言

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