Sqlalchemy is easy to use

First, sqlalchemy connects to the database.

Installation:

Pip install sqlalchemy

Sqlalchemy View version:

Import sqlalchemy

Sqlalchemy.__version__

Sqlalchemy connection to the database:

From sqlalchemy import create_engine

HOST='127.0.0.1'

PORT='3306'

DATABASE='test'

USERNAME='test'

PASSWORD='pass'

DB_URL = 'mysql+pymysql:// {}: {} @ {}: {} / {}? charset=utf8'.format (

USERNAME, PASSWORD, HOST, PORT, DATABASE

)

Engin = create_engine (DB_URL, echo=False)

The simple process for sqlalchemy to create a table:

1. Create a base class

From sqlalchemy.ext.declarative import declarative_base

Base = declarative_base ()

two。 Create a class

From sqlalchemy import Column, Integer, String

Class User (Base):

_ _ tablemame__ = 'users' # the name of the data table

Id = Column (Integer, Sequence ('user_id_seq'), Primary_key=True) # set as the primary key

Name = Column (String (20), nullable=False) # non-empty

Password = Column (String (255), nullable=False)

Create a table:

Base.metadata.create_all (engine)

Create an object

Zs_user = User (name='zs', fullname='ZhangSan', password='password')

Zs.name

Zs

Create Session

From sqlalchemy.orm import sessionmaker

Session = sessionmaker (bind=engine)

Add update object

Add a zs_user object to the session

Session.add (zs_user)

Through conditional query

Zs = session.query (User). Filter_by (name='zs'). First ()

You can use the add_all () function to add multiple User objects at one time,

Session.add_all (

User (name='ls', fullname='lisi', password='pass')

User (name='ww', fullname='wangwu', password='pass')

)

View the status waiting for submission:

Session.new

Commit changes to the database:

Session.commit ()