大整数
class BigInteger(Integer):
"""A type for bigger ``int`` integers.
Typically generates a ``BIGINT`` in DDL, and otherwise acts like
a normal :class:`.Integer` on the Python side.
"""
__visit_name__ = 'big_integer'
BIGINT
class BIGINT(BigInteger):
"""The SQL BIGINT type."""
__visit_name__ = 'BIGINT'
但是 Column(BigInteger) 和 Column(BIGINT) 都可以工作,它们都在postgresql中定义了一个bigint。如何区分它们?