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 delete(self, dn, controls=None):

        self.result = { 'dn' : '',
                        'referrals' : None,
                        'description' : 'success',
                        'result' : 0,
                        'message' : '',
                        'type' : 'addResponse'}

        # Check to see if the user exists in the directory
        try:
            index = self._find_user(dn)
        except StopIteration:
            # If we get here the user doesn't exist so continue
            self.result["description"] = "failure"
            self.result["result"] = 32
            self.result["message"] = "Error no such object: {0}".format(dn)
            return False

        # Delete the entry object for the user
        self.directory.pop(index)

        # Attempt to write changes to disk
        with open(DIRECTORY, 'w+') as f:
            f.write(str(self.directory))

        return True