过滤关系加入 sqlalchemy

Question

我有三个模型：

class ColumnModel(Base):

__tablename__ = "column"

board_id = Column(Integer, ForeignKey('board.id'))
tasks_order = Column(ARRAY(Integer))

board = relationship("Board", back_populates="columns")
tasks = relationship("Task", back_populates="column")


class Task(Base):

__tablename__ = "task"

column_id = Column(Integer, ForeignKey('column.id'))
column = relationship("ColumnModel", back_populates="tasks")



class Board(Base):
__tablename__ = "board"

columns = relationship("ColumnModel", back_populates="board")

现在我的代码是：

board = db.query(self.model) \
        .outerjoin(ColumnModel)\
        .outerjoin(Task)\\
        .all()

查询是：

SELECT board.id AS board_id, board.title AS board_title, board.columns_order AS board_columns_order FROM board LEFT OUTER JOIN "column" ON board.id = "column".board_id LEFT OUTER JOIN task ON "column".id = task.column_id WHERE board.id = %(id_1)s

添加另一个过滤器（）将只过滤板 model，而不是 ColumnModel 或任务。 但我想通过 id 过滤例如 Task：filter(Task.id.in_((1, 2, 3))) 或只是 (Task.id==4)