Used by Variable/Connection.

https://github.com/apache/airflow/blob/894741e311ffd642e036b80d3b1b5d53c3747cad/airflow/secrets/metastore.py#L32

:param schema: The schema.
    :param port: The port number.
    :param extra: Extra metadata. Non-standard data such as private/SSH keys can be saved here. JSON
        encoded object.
    :param uri: URI address describing connection parameters.
    """
    EXTRA_KEY = "__extra__"
    __tablename__ = "connection"
    id = Column(Integer(), primary_key=True)
    conn_id = Column(String(ID_LEN), unique=True, nullable=False)
    conn_type = Column(String(500), nullable=False)
    description = Column(Text().with_variant(Text(5000), "mysql").with_variant(String(5000), "sqlite"))
    host = Column(String(500))
    schema = Column(String(500))
    login = Column(String(500))
    _password = Column("password", String(5000))
    port = Column(Integer())
    is_encrypted = Column(Boolean, unique=False, default=False)
    is_extra_encrypted = Column(Boolean, unique=False, default=False)
    _extra = Column("extra", Text())
    def __init__(
        self,
        conn_id: str | None = None,
        conn_type: str | None = None,
        description: str | None = None,
        host: str | None = None,
        login: str | None = None,
        password: str | None = None,
        schema: str | None = None,
        port: int | None = None,