Peewee 简明教程

Peewee - Atomic Transactions

Peewee 的 database 类拥有 atomic() 方法，它创建了一个上下文管理器。它开启一个新事务。在上下文块内部，可以根据事务是否成功完成或遇到异常来提交或回滚事务。

Peewee’s database class has atomic() method that creates a context manager. It starts a new transaction. Inside the context block, it is possible to commit or rollback the transaction depending upon whether it has been successfully done or it encountered exception.

with db.atomic() as transaction:
   try:
      User.create(name='Amar', age=20)
      transaction.commit()
   except DatabaseError:
      transaction.rollback()

atomic() 也可作为装饰器使用。

The atomic() can also be used as decorator.

@db.atomic()
def create_user(nm,n):
   return User.create(name=nm, age=n)

create_user('Amar', 20)

多个原子事务块也可以嵌套。

More than one atomic transaction blocks can also be nested.

with db.atomic() as txn1:
   User.create('name'='Amar', age=20)

   with db.atomic() as txn2:
      User.get(name='Amar')