peewee orm 表的创建，以及peewee-async 异步的使用

浅浅的花香味﹌ 2022-02-01 20:37 430阅读 0赞

# peewee 创建表 #

pip install pymysql
    pip install peewee

from peewee import *
    from peewee import Model
    
    db = MySQLDatabase("message",host="127.0.0.1",port=3306,user="root",password="root")
    # 数据库名称
    
    class Goods(Model):
        # id 没有添加主键，会自动添加id
        name = CharField(max_length=100,verbose_name="商品名字",index=True)
        click_num = IntegerField(default=0,verbose_name="点击数")
        goods_num = IntegerField(default=0,verbose_name="库存")
        price = FloatField(default=0.0,verbose_name="商品价格")
        brief = TextField(verbose_name="商品简介")
        
        
        class Meta:
            database = db
            table_name = "goods"
    
    def init_table():
        # 将想要创建的数据库表，放入list中
        db.create_tables([Goods])
    
    if __name__ == "__main__":
        init_table()

# 优化一下 #

from peewee import *
    from peewee import Model
    
    # 数据库连接
    db = MySQLDatabase("message",host="127.0.0.1",port=3306,user="root",password="root")
    
    
    # 基类
    class BaseModel(Model):
        add_time = DateTimeField(default=datetime.now(),verbose_name="添加时间")
        class Meta:
            database = db
    
    # 供应商
    class Suppliter(Model):
    	name = CharField(max_length=100,verbose_name="供应商名字",index=True)
        address =  CharField(max_length=100,verbose_name="联系地址")
        phone =  CharField(max_length=111,verbose_name="联系电话")
        class Meta:
            # database = db 每次添加太麻烦了，我们去写一个基类
            table_name = "suppliter"
            
    
    class Goods(Model):
        # id 没有添加主键，会自动添加id
        
        name = CharField(max_length=100,verbose_name="商品名字",index=True)
        click_num = IntegerField(default=0,verbose_name="点击数")
        goods_num = IntegerField(default=0,verbose_name="库存")
        price = FloatField(default=0.0,verbose_name="商品价格")
        brief = TextField(verbose_name="商品简介")
        # 外键,保存在数据库里的名字叫 suppliter_id 
        suppliter = ForeignKeyField(Suppliter,verbose_name="商家".backref="goods")
        
        class Meta:
            table_name = "goods"
    
    def init_table():
        # 将想要创建的数据库表，放入list中
        db.create_tables([Goods,Suppliter])
    
    if __name__ == "__main__":
        init_table()

# peewee集成到tornado中 #

使用异步的orm,async peeww

pip install aiomysql
    pip install --pre peewee-async

import asyncio
    from peewee import *
    from peewee import Model
    import peewee-async
    
    # 数据库连接
    # db = MySQLDatabase("message",host="127.0.0.1",port=3306,user="root",password="root")
    database = peewee_async.PostgresqlDatabase(database="db_name",
                     host="127.0.0.1",port=3306,user="root",password="root")
    
    # 异步的创建数据库
    objects = peewee_async.Manager(databases)
    database.set_allow_sync(False) # 是否设置为同步，False异步
    
    
    # 基类
    class BaseModel(Model):
        add_time = DateTimeField(default=datetime.now(),verbose_name="添加时间")
        class Meta:
            database = database # 之前的db
    
    # 供应商
    class Suppliter(Model):
    	name = CharField(max_length=100,verbose_name="供应商名字",index=True)
        address =  CharField(max_length=100,verbose_name="联系地址")
        phone =  CharField(max_length=111,verbose_name="联系电话")
        class Meta:
            # database = db 每次添加太麻烦了，我们去写一个基类
            table_name = "suppliter"
            
    
    class Goods(Model):
        # id 没有添加主键，会自动添加id
        
        name = CharField(max_length=100,verbose_name="商品名字",index=True)
        click_num = IntegerField(default=0,verbose_name="点击数")
        goods_num = IntegerField(default=0,verbose_name="库存")
        price = FloatField(default=0.0,verbose_name="商品价格")
        brief = TextField(verbose_name="商品简介")
        # 外键,保存在数据库里的名字叫 suppliter_id 
        suppliter = ForeignKeyField(Suppliter,verbose_name="商家".backref="goods")
        
        class Meta:
            table_name = "goods"
    
    # 异步创建数据库
    async def handler():
        await object.create(Goods,name="xxx",suppliter="ppp")
        
    async def get_goods():
        # object.excute 异步执行sql查询
        # Goods.select() 同步的查询方法 
        # 放入到object.excute 执行
        goods_list = await object.excute(Goods.select())
        
    if __name__ == "__main__":
        # 异步创建数据库，协程不能直接启动，需要配合对应的方法
        loop = asyncio.get_envent_loop()
        loop.run_until_complete(handler())
        loop.close()

# 这个查询语句，不会真正的执行，只有当我们for循环它，或者索引等操作它的时候，才会去执行
    # 它返回的是 modelselect对象
    question_query = question_query.filter(Question.category==c)
    question_query = question_query.order_by(Question.answer_nums.desc())