当值有时为空时参数化SQL查询

pyodbc 我可以这样参数化查询;

value = "testval"

query = \
    """
    SELECT *
    FROM TestTable
    WHERE Column = ?;
    """

cursor.execute(query, value)

但问题是如果 value 如果为None,则查询应如下所示;

value = None

query = \
    """
    SELECT *
    FROM TestTable
    WHERE Column IS NULL;
    """

cursor.execute(query)

那么当 价值

value = get_value()  # can return a string or None

query = \
    """
    SELECT *
    FROM TestTable
    WHERE Column ???????????
    """

cursor.execute(query, value)