研究下面的tnsnames.ora文件: test =(description = (address_list =(address=(protocol=tcp)(host=serv2)(port=1521)) ) (connect_data=(service_name =prod) )) prod=(description= (address_list= (address=(protocol=tcp)(host=servl)(port=1521)) ) (connect_data =(service_name=prod) )) dev=(description= (address_list=(address= (protocol=tcp)(host=serv2)(port=1521)) ) (connect_data=(service_name=dev) )) 有关连接字符串test、prod和dev,下面哪些语句的描述是正确的(选择所有正确的答案)?
A.三个都正确
B.只有将实例设置为动态实例注册时,所有三个才能成功
C.测试连接将失败,因为连接字符串与服务名不匹配
D.serv2上将出现端口冲突现象,因为prod和dev尝试使用同一端口