经常遇到PL/SQL Developer等依赖Client的工具无法连接Oracle数据库服务器的问题。至今也没完全理清楚,先发个帖总结一下目前的方
经常遇到PL/SQL Developer等依赖Client的工具无法连接Oracle数据库服务器的问题。至今也没完全理清楚,先发个帖总结一下目前的方法,后面会不断完善。
方法一:
重启Oracle服务器端相关服务,包括...TNSListener,所用的数据库实例的服务。可直接在Windows的“服务”中重启。或者(可使用的命令):
lsnrctl stop
lsnrctl start
lsnrctl reload
sqlplus / as sysdba;
startup;
这个方法试过多次有效,但原因未知,求真相。
方法二:
使用Net Configuration Assist配置服务器端和客户端。
Oracle服务器端需要设置listener(监听程序),设置结果影响listener.ora(...\db_1\NETWORK\ADMIN)。Client端(客户端)需要配置“本地Net服务名配置”,可能影响tnsnames.ora和sqlnet.ora两个文件。若是Oracle Client,,则文件位置是...\client_1\NETWORK\ADMIN
方法三:
若装有Oracle Client,则可使用Enterprise Manager Console添加数据库连接,会修改tnsnames.ora文件(...\client_1\NETWORK\ADMIN)。
方法四:
查看sqlnet.ora中是否有NAMES,DIRECTORY_PATH等,可能与此有关。
# sqlnet.ora Network Configuration File: C:\oracle\product\10.2.0\db_1\network\admin\sqlnet.ora
# Generated by Oracle configuration tools.
# This file is actually generated by netca. But if customers choose to
# install "Software Only", this file wont exist and without the native
# authentication, they will not be able to connect to the database on NT.
SQLNET.AUTHENTICATION_SERVICES= (NTS)
NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)
注意:
1. Enterprise Manager Console与Net Configuration Assist添加的数据库连接描述符不同,前者为...CONNECT_DATA=(SID=...)(SERVER=...)...,后者为...(SERVICENAME=...)...。
2. Enterprise Manager Console中删除一条连接后,tnsnames.ora中的描述字符串不会自动删除;Net Configuration Assist中删除一条本地Net服务配置后,tnsnames.ora文件中对应的描述字符串会自动删除。
3. 若安装配置OWB(Oracle Warehouse Builder),则文件位置是...\client_1\NETWORK\ADMIN

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