Server question that arises is running the project can not access the oracle database connection, enter the user name and password stuck with plsql, unable to connect. But the command window to normal operating oracle database, oracle of view and restart the service, there is no exception, the following problems arise when running tnsping orcl command, has been in the connection, still can not connect successfully:
Check the parameter file, the instance name is no mistake, no problem listening through all aspects of the investigation and the Internet to find, because the oracle listen to finalize the log file is too large (4G), resulting in tnsping barrier.
Solution: Stop oracle service, will listener.log logs cut backup (also available through oracle commands to perform backups), restart the service, the problem is solved! ~