python - 过滤 False 列值返回 True

Question

我有两个表，我正在对第二个表的位列进行左连接。过滤器返回该位为 False 的列。但是，当我稍后在循环中检查该值时，它显示为 true。

from sqlalchemy import create_engine
from sqlalchemy.orm import Session
from sqlalchemy import Column, String, Integer, Boolean, ForeignKey, or_
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship
from sqlalchemy.orm.exc import NoResultFound
# from sqlalchemy.exc import DataError
Base = declarative_base()

class BoardGame(Base):
    __tablename__ = 'game_detail'
    id = Column(Integer, primary_key=True)
    name = Column(String)
    description = Column(String)
    process = relationship('Process', uselist=False, back_populates='game_detail')

    def __repr__(self):
        return "<BoardGame(id='{}', name='{}', description='{}'".format(
            self.id, self.name, self.description
        )

class Process(Base):
    __tablename__ = 'process'
    game_id = Column(Integer, ForeignKey('game_detail.id'), primary_key=True)
    description_bigram = Column(Boolean)
    game_detail = relationship('BoardGame', back_populates='process')

sa_engine = create_engine('mysql+pymysql://bgg:blahblahblah@localhost:49000/boardgamegeek?charset=utf8mb4', pool_recycle=3600)
session = Session(bind=sa_engine)

# Set the scripts execution range of data
maximum_games_to_process = 1

for game in session.query(BoardGame.id, Process.description_bigram).join(Process, isouter=True).filter(Process.description_bigram.is_(False)).limit(maximum_games_to_process):
    print('description_bigram', type(game.description_bigram), game.description_bigram)
    print(game)

运行上面得到我

description_bigram <class 'bool'> True
(1, True)

但是查看 HeidiSQL 中的数据却让我看到了另一种情况。

game_id;description_bigram
1;0
2;1
3;0
4;0
5;1

这是HeidiSQL中显示的进程表的创建代码

CREATE TABLE `process` (
    `game_id` INT(11) NOT NULL,
    `description_bigram` BIT(1) NOT NULL,
    PRIMARY KEY (`game_id`),
    CONSTRAINT `FK__GAME_ID_DESCRIPTION` FOREIGN KEY (`game_id`) REFERENCES `game_detail` (`id`) ON UPDATE NO ACTION ON DELETE NO ACTION
)
COLLATE='utf8_unicode_ci'
ENGINE=InnoDB

我已经看到一些帖子回避了 SQLAlchemy 的布尔列问题，人们已经更改了他们的表和代码以使用整数（链接仅与我的情况相似）。我确信这会起作用，但我还有其他程序可以很好地处理位列和表布尔定义，所以我不确定为什么这个程序不起作用。引擎盖下有什么我可以看的吗？

这是 SQLAlchemy 创建的查询

SELECT game_detail.id AS game_detail_id, process.description_bigram AS process_description_bigram
FROM game_detail LEFT OUTER JOIN process ON game_detail.id = process.game_id
WHERE process.description_bigram IS false

我已经尝试了一些方法来尝试让该列注册其正确的值，而我只是一直以它为真而告终。

Python 是 3.6.5 版；SQLAlchemy 是 1.2.7；10.3.13-MariaDB

标签： pythonpython-3.xsqlalchemymariadb