ORA-12514:TNS:监听程序当前无法识别连接描述符中请

ORA-12514:TNS:监听程序当前无法识别连接描述符中请求的服务

PL/SQL连接Oracle数据库的时候 报"ORA-12514: TNS:监听程序当前无法识别连接描述符中请求的服务" 错误

本例原因：

安装Oracle时一般默认实例都是orcl，发现有人不按套路出牌，改了名字，如图

解决方法：

在Oracle安装目录 找到listener.ora文件 路径为 D:\oracle\product\11.2.0\dbhome_1\NETWORK\ADMIN

(根据自己情况查找) 修改：

# listener.ora Network Configuration File: D:\oracl\product\11.2.0\dbhome_1\network\admin\listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = CLRExtProc)
(ORACLE_HOME = D:\oracle\product\11.2.0\dbhome_1)
(PROGRAM = extproc)
(ENVS = "EXTPROC_DLLS=ONLY:D:\oracle\product\11.2.0\dbhome_1\bin\oraclr11.dll")
)
(SID_DESC =
(GLOBAL_DBNAME = JTW)
(ORACLE_HOME = D:\oracle\product\11.2.0\dbhome_1)
(SID_NAME = JTW)
)
)

LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
)
)

红色部分为新添加内容，JTW为监听的实例名

然后修改(添加)instantclient_11_2\network\admin\tnsnames.ora

MyOracle =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = jtw)
    )
  )

重启Oracle监听