What should I do if Oracle cannot connect?
Solutions for oracle failure to connect:
If you encounter the same problem, then you might as well take a look at some of the solutions I introduce here
1. Cause: The database is not closed properly
Solution: Close the database and then restart it. Every time our CRM reports this error, it is usually caused by the failure to close it properly last time, so as long as it is closed after Just open it again. The details are as follows:
Open the command window:
sqlplus “sys/dba as sysdba”[这里sys是用户名,dba是密码,如果用系统用户,即sys登陆,则必须后面跟上as sysdba]
In this step, you can also directly open the sqlplus command window and enter the user name and password
shutdown abort
Directly use the strongest method of abort to close it, because the amount of data in our oracle database is already relatively large. If you use a gentle method immediately, it may get stuck there. Don't move. Of course, if your data volume is relatively small, you can choose a gentle method, which will not easily damage the database.
startup
The database will now be started. Try accessing it again. There should be no problem.
Recommended tutorial: "Oracle Tutorial》
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