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  • sqlalchemy的filter使用

    原文出处:sqlalchemy的filter使用

    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'
    #
    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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  • 原文地址:https://www.cnblogs.com/kaerxifa/p/13391722.html
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