flask笔记：5：数据库

CSRF_ENABLED=True
SECRET_KEY='you-will-never-guess'
import os
basedir = os.path.abspath(os.path.dirname(__file__))
SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'app.db')
SQLALCHEMY_MIGRATE_REPO = os.path.join(basedir, 'db_repository')
SQLALCHEMY_TRACK_MODIFICATIONS=True
#db文件创建在与创建脚本同一目录下
# SQLALCHEMY_DATABASE_URI是the Flask-SQLAlchemy必需的扩展。这是我们的数据库文件的路径。
# SQLALCHEMY_MIGRATE_REPO 是用来存储SQLAlchemy-migrate数据库文件的文件夹。
#SQLALCHEMY_TRACK_MODIFICATIONS 不设为True会报错(貌似段代码没有也能正常运行)

from flask import Flask
from flask.ext.sqlalchemy import SQLAlchemy
app=Flask(__name__)
app.config.from_object('config')
db=SQLAlchemy(app)
from app import views,models
#导入Flask-SQLAlchemy
#创建了一个 db 对象，这是我们的数据库
#导入一个新的模块，叫做 models

from app import db

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    nickname = db.Column(db.String(64), index=True, unique=True)
    email = db.Column(db.String(120), index=True, unique=True)
    posts = db.relationship('Post', backref='author', lazy='dynamic')

    def __repr__(self):
        return '<User %r>' % (self.nickname)

class Post(db.Model):
    id = db.Column(db.Integer, primary_key = True)
    body = db.Column(db.String(140))
    timestamp = db.Column(db.DateTime)
    user_id = db.Column(db.Integer, db.ForeignKey('user.id'))

    def __repr__(self):
        return '<Post %r>' % (self.body)

from app import db
db.create_all()
#create_all( )是创建数据库

from app import db, models

def add_com (u):
    db.session.add(u)
    db.session.commit()

u = models.User(nickname='john', email='john@email.com')
add_com(u)
w=models.User(nickname='susan', email='susan@email.com')
add_com(w)
#session.add( )添加数据
#session.commit( )提交事务

import datetime
from app import db, models

u = models.User.query.get(1)
p = models.Post(body='my first post!', timestamp=datetime.datetime.utcnow(), author=u)
db.session.add(p)
db.session.commit()
#authou就是Post数据类里的user_id(应该是的)

from app import db, models
users = models.User.query.all()
print users
for u in users :
    print u.id,u.nickname
e=models.User.query.get(1)
print e
p=models.User.query.filter_by(nickname="john").first()
print p.id
print p.email
d=models.User.query.filter(models.User.email.endswith('@email.com')).all()
print d

from app import db, models
u = models.User.query.get(1)
print u
posts = u.posts.all()
print posts
e=models.User.query.get(2)
print e.posts.all()

from app import db, models
users = models.User.query.all()
for u in users:
    db.session.delete(u)
posts = models.Post.query.all()
for p in posts:
    db.session.delete(p)
db.session.commit()
#session.delete( )删除