ORA-12523: TNS: 监听程序无法找到适用于客户机连接的例程

这是要修改客户端配置tnnames.ora文件，你试一下如下的修改

demo =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 主机名)(PORT = 端口号))
)
(CONNECT_DATA =
(SERVER = SHARED)

  (SID=demo)
)

)