【Flask】filter 常用查询条件

1. equal    2. not equal  3. like, ilike  4.in  5. not in 

6. is null  7. is not null  8. and  9. or

#### 如果想查看orm底层查询sql可以在filter函数后面不写人物的函数如：

articles = session.query(Article).filter(Article.title != 'title0')

 

 

 1 # coding:utf-8
 2 # Author: liangjun.chen
 3 
 4 from datetime import date
 5 from datetime import datetime
 6 from datetime import time
 7 from random import random
 8 from sqlalchemy import create_engine, Column, Integer, String, Float, Text, and_, or_
 9 
10 from sqlalchemy.ext.declarative import declarative_base
11 from sqlalchemy.orm import sessionmaker
12 
13 HOSTNAME = '127.0.0.1'
14 PORT = 3306
15 DATABASE = 'sqlalchemy_first'
16 USERNAME = 'root'
17 PASSWORD = '123456'
18 
19 DB_URI = 'mysql+pymysql://{username}:{password}@{host}:{port}/{dbname}?charset=utf8'.format(
20         username=USERNAME, password=PASSWORD, host=HOSTNAME, port=PORT, dbname=DATABASE
21 )
22 engine = create_engine(DB_URI)
23 Base = declarative_base(engine)
24 Session = sessionmaker(engine)
25 session = Session()
26 
27 
28 class Article(Base):
29     __tablename__ = 'article'
30     id = Column(Integer, primary_key=True, autoincrement=True)
31     title = Column(String(50), nullable=False)
32     price = Column(Float, nullable=False)
33     content = Column(Text)
34 
35     def __repr__(self):
36         return "Article".format(self.title, self.price)
37 
38 
39 # 1. equal
40 article = session.query(Article).filter(Article.id == 1).first()
41 print article
42 
43 # 2. not equal
44 articles = session.query(Article).filter(Article.title != 'title0').all()
45 print articles
46 
47 # 3. like, ilike->不区分大小写
48 articles = session.query(Article).filter(Article.title.like('title%')).all()
49 print articles
50 
51 # 4. in
52 print '-' * 20
53 articles = session.query(Article).filter(Article.title.in_(['title1', 'title2'])).all()
54 print articles
55 
56 # 5. not in
57 print '-' * 20
58 articles = session.query(Article).filter(~Article.title.in_(['title2', 'title1'])).all()
59 articles2 = session.query(Article).filter(Article.title.notin_(['title2', 'title1'])).all()
60 
61 print articles
62 print articles2
63 
64 # 6. is null
65 print '-' * 20
66 articles = session.query(Article).filter(Article.content == None).all()
67 print articles
68 
69 # 7. is not null
70 print '-' * 20
71 articles = session.query(Article).filter(Article.content != None).all()
72 print articles
73 
74 # 8. and
75 print '-' * 20
76 articles = session.query(Article).filter(Article.title == 'title0', Article.content == 'test').all()
77 articles_2 = session.query(Article).filter(and_(Article.title == 'title0', Article.content == 'test')).all()
78 print articles
79 print articles_2
80 
81 # 9. or
82 print '-' * 20
83 articles = session.query(Article).filter(or_(Article.title == 'title1', Article.content == 'test')).all()
84 print articles

 

转载于:https://www.cnblogs.com/chen0427/p/8635650.html