peewee 很适宜用来解决一些简略的 crud 工作,如果是简单的查问语句,我更加喜爱用 raw sql 来解决
用 join 查问来举例子:
models.py
from peewee import *
import settings
host = settings.DATABASE.host
port = settings.DATABASE.port
username = settings.DATABASE.username
password = settings.DATABASE.password
database_name = settings.DATABASE.database
db = MySQLDatabase(
database=database_name,
host=host,
port=port,
user=username,
password=password
)
class User(Model):
id = AutoField()
name = CharField(max_length=255, null=False)
created_at = DateTimeField(
null=False,
constraints=[SQL('DEFAULT CURRENT_TIMESTAMP')],
help_text='应用数据库工夫'
)
updated_at = DateTimeField(
null=False,
constraints=[SQL('DEFAULT CURRENT_TIMESTAMP'),
SQL('ON UPDATE CURRENT_TIMESTAMP'),
]
)
class Meta:
database = db
table_name = 'account'
class Order(Model):
"""订单信息表"""
id = AutoField(primary_key=True)
user_id = IntegerField(null=False, unique=False, index=True)
product_id = IntegerField(null=False, unique=False)
activity_id = IntegerField(null=False, unique=False)
is_paid = BooleanField(null=False, unique=False, default=False)
created_at = DateTimeField(
null=False,
constraints=[SQL('DEFAULT CURRENT_TIMESTAMP')]
)
updated_at = DateTimeField(
null=False,
constraints=[SQL('DEFAULT CURRENT_TIMESTAMP'),
SQL('ON UPDATE CURRENT_TIMESTAMP'),
]
)
class Meta:
database = db
table_name = 'order'
# http://docs.peewee-orm.com/en/latest/peewee/models.html?highlight=table%20generation#multi-column-indexes
indexes = (
# create a unique on, 限购一次
(('user_id', 'product_id', 'activity_id'), True),
)
查问一些数据
order
表
insert into `order` (user_id,product_id,activity_id,is_paid) values (1,2,3,0)
insert into `order` (user_id,product_id,activity_id,is_paid) values (2,3,4,0)
account
表
insert into `account` (name) values ('jike')
insert into `account` (name) values ('ponponon')
看看插入后的后果
MySQL root@192.168.31.245:seckill> select * from account;
+----+----------+---------------------+---------------------+
| id | name | created_at | updated_at |
+----+----------+---------------------+---------------------+
| 1 | jike | 2022-04-06 13:26:28 | 2022-04-06 13:31:34 |
| 2 | ponponon | 2022-04-06 13:26:35 | 2022-04-06 13:26:35 |
+----+----------+---------------------+---------------------+
2 rows in set
Time: 0.005s
各两条
MySQL root@192.168.31.245:seckill> select * from `order`
+----+---------+------------+-------------+---------+---------------------+---------------------+
| id | user_id | product_id | activity_id | is_paid | created_at | updated_at |
+----+---------+------------+-------------+---------+---------------------+---------------------+
| 1 | 1 | 2 | 3 | 0 | 2022-04-06 13:25:19 | 2022-04-06 13:25:19 |
| 2 | 2 | 3 | 4 | 0 | 2022-04-06 13:25:28 | 2022-04-06 13:25:28 |
+----+---------+------------+-------------+---------+---------------------+---------------------+
2 rows in set
Time: 0.007s
应用单元测试的脚本来验证
import unittest
from loguru import logger
from models import db
from pymysql.cursors import Cursor
class TestProject(unittest.TestCase):
def peewee_exec_raw_sql(self):
"""python -m unittest tests.TestProject.peewee_exec_raw_sql"""
# cursor = db.cursor()
with db.cursor() as cursor:
cursor: Cursor
sql = """
SELECT
`account`.`id`,
`account`.`name`,
`order`.`product_id`
FROM
`account`
INNER JOIN `order` ON (`account`.`id` = `order`.`user_id`)
"""
cursor.execute(sql)
rows: tuple[tuple] = cursor.fetchall()
for row in rows:
logger.debug(row)
执行后果
─➤ python -m unittest tests.TestProject.peewee_exec_raw_sql
2022-04-06 13:37:20.893 | DEBUG | tests:peewee_exec_raw_sql:36 - (1, 'jike', 2)
2022-04-06 13:37:20.894 | DEBUG | tests:peewee_exec_raw_sql:36 - (2, 'ponponon', 3)
.
----------------------------------------------------------------------
Ran 1 test in 0.005s
参考文章:
Python 编程:peewee 执行多条原生 sql 语句
This document describes changes to be aware of when switching from 2.x to 3.x.