Python Account示例

示例#1

def create_records():
    session = create_session()

    account1 = Account(name='account1', amount=Decimal('11.11'))
    account2 = Account(name='account2', amount=Decimal('22.22'))

    session.add(account1)
    session.add(account2)

    session.commit()

示例#2

def first_flow(print_function):
    session = create_session()

    print_function('Adding account 3...')
    account3 = Account(name='account3', amount=Decimal('33.33'))
    session.add(account3)

    print_function('Flushing changes to the DB...')
    session.flush()

    print_function('Sleeping...')
    sleep(5)
    print_function('Waking up...')

    print_function('We didn\'t commit anything...')

示例#3

文件： 2_2_dirty_write_continuation.py 项目： solshanetskyi/lunch_and_learn_transactions

def first_flow(print_function):
    session = create_session()

    print_function('Adding account 3...')
    account3 = Account(name='account3', amount=Decimal('33.33'))
    session.add(account3)

    print_function('Flushing changes to the DB...')
    session.flush()

    print_function('Sleeping...')
    sleep(5)
    print_function('Waking up...')

    print_function('Rolling back...')
    session.rollback()
    print_function('Rolled back!!')

示例#4

def second_flow(print_function):
    session = create_session()

    print_function('Adding new account at the meantime...')
    account3 = Account(name='account3', amount=Decimal('33.33'))
    session.add(account3)

    account1 = session.query(Account).filter(Account.name == 'account1').one_or_none()
    account2 = session.query(Account).filter(Account.name == 'account2').one_or_none()

    if account1:
        print_function('Updating existing account at the meantime...')
        account1.name = 'Updated from second flow'
        session.commit()

    if account2:
        print_function('Deleting existing account at the meantime...')
        session.delete(account2)

    session.commit()
    print_function('Committed!!')

示例#5

文件： 0_session_basics.py 项目： solshanetskyi/lunch_and_learn_transactions

from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

from account_model import Account
from common import print_first

connecting_string = f'mysql+mysqldb://root:[email protected]:52000/lunch_and_learn'
engine = create_engine(connecting_string,
                       echo=True,
                       connect_args={'connect_timeout': 10})

Session = sessionmaker(bind=engine, autoflush=True)
session = Session()

account1 = Account(name='account1', amount=Decimal('11.11'))
account2 = Account(name='account2', amount=Decimal('22.22'))

session.add(account1)
session.add(account2)

session.flush()
# session.query(Account).count()

print_first('Sleeping..')
sleep(7)
print_first('Waking up!')

print_first('Committing...')
session.commit()
print_first('Committed')