关于数据库连接问题的一般解决方法
一般步骤：
验证网络连接
ping IP-Address
验证网络名称解析
ping symbolic-hostname
验证net8连接和名称解析
tnsping connect-string
验证数据库实例可用性
SQL*Plus
常见问题：
TNS-12154 "TNS:could not resolve service name"
TNS-12545 "TNS:name lookup failure"
TNS-12203 "TNS:unable to connect to destination"
ORA-03113 "end-of-file on communication channel"
Solution : either the specified HOST, the Oracle database instance, or your particular Oracle server process terminated
abnormally after connection established
either the specified HOST machine is 'down' or the SQL*Net listener at the specified HOST and PORT is not running
not a valid network hostname; either 'typo' or a network DNS failure (try using only IP address instead)
connect string you specified is not in TNSNAMES.ORA
HOST specified the SQL*Net
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/6906/viewspace-21601/ ，如需转载，请注明出处，否则将追究法律责任。
