from flask import Flask, jsonify, json
from sqlalchemy import create_engine, Column, Integer, String, DateTime, Float, func, and_, or_
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from datetime import datetime
# 连接数据库字符串
DB_URI = "mysql://root:123456@127.0.0.1/pyDemo"
engine = create_engine(DB_URI)
# 判断是否连接成功
engine.connect()
# 创建ORM
Base = declarative_base(engine)
# 创建回话
session = sessionmaker(engine)()
class Article(Base):
# 表名字
__tablename__ = 'Article'
# 列
id = Column(Integer, primary_key=True, autoincrement=True)
# read_count = Column(Integer, default=0)
title = Column(String(50), default='1111')
content = Column(String(50))
price = Column(Float, nullable=False)
# 查询条件
# 1.equal
res = session.query(Article).filter(Article.id == 21).first()
# print(res)
# 2.notequal
res = session.query(Article).filter(Article.id != 21).all()
# print(res)
# 3.like & ilike不区分大小写
res = session.query(Article).filter(Article.title.like('title%')).all()
# print(res)
# 4.in
res = session.query(Article).filter(Article.title.in_(['title0', 'title1'])).all()
# print(res)
# 5.not in
res = session.query(Article).filter(~Article.title.in_(['title0', 'title1'])).all()
# print(res)
res = session.query(Article).filter(Article.title.notin_(['title0', 'title1'])).all()
# print(res)
# 6.isnull
res = session.query(Article).filter(Article.content == None).all()
# print(res)
# 7.is not null
res = session.query(Article).filter(Article.content != None).all()
# print(res)
# 8 and
res = session.query(Article).filter(Article.content == None, Article.title.notin_(['title0', 'title1'])).all()
# print(res)
res = session.query(Article).filter(and_(Article.content == None, Article.title.notin_(['title0', 'title1']))).all()
# print(res)
# 9 or
res = session.query(Article).filter(
or_(Article.content != None, Article.title.notin_(['title0', 'title1', 'title5']))).all()
print(res)
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