def robotsrulesetOfDomain(self, domain):
		'''检查domain是否在数据库中,
			否 --> (False, None)
			是 --> (True, 数据库中存储的robots.txt内容)
		'''
		exist = False
		cur = self.conn.cursor()
		# 是否存在
		cur.execute("SELECT 1 FROM Domains WHERE domain=?", (domain,))
		if cur.fetchone() :
			exist = True
		# 存在的话,结果是什么
		cur.execute("SELECT rules FROM Domains,Rulesets "
			"WHERE domain=? AND Domains.did=Rulesets.did"
			,(domain,) )
		ruleset = cur.fetchone()
		return (exist, ruleset)
def _check_version(version, filename):
    major, minor = version.split('.')

    try:
        major = int(major)
    except ValueError as e:
        raise TransactionReplayError(
            filename,
            _('Invalid major version "{major}", number expected.').format(major=major)
        )

    try:
        int(minor)  # minor is unused, just check it's a number
    except ValueError as e:
        raise TransactionReplayError(
            filename,
            _('Invalid minor version "{minor}", number expected.').format(minor=minor)
        )

    if major != VERSION_MAJOR:
        raise IncompatibleTransactionVersionError(
            filename,
            _('Incompatible major version "{major}", supported major version is "{major_supp}".')
                .format(major=major, major_supp=VERSION_MAJOR)
        )