Check the status of Oracle database in Linux.

To check the status of the Oracle database, you can use the following command:

1. Log in to the Oracle user account on the Linux server.
2. Open the terminal window.
3. Use the following command to start the Oracle instance:
4. Log in to sqlplus as the sysdba user.
5. Use the following command to check the status of the database instance:
6. Show the status of the current instance in the view “v$instance”.
7. If the result displays as “OPEN,” it means the database instance is running. If the result displays as “STARTED” or “MOUNTED,” it means the database instance has been started but not fully opened yet.
8. Additionally, if you want to view detailed information about the database instance, you can use the following command:
9. Choose the instance_name, host_name, startup_time, and status columns from the v$instance table.
10. Use the following command to view the overall status of the database:
11. Display the name, open mode, and log mode of the database from the v$database view.
12. The “open_mode” column in the results will display the database’s open mode, which can have values of “READ WRITE” (read-write mode) and “READ ONLY” (read-only mode).
13. The column “log_mode” in the result will display the log mode of the database, with possible values being “ARCHIVELOG” (archive log mode) and “NOARCHIVELOG” (non-archive log mode).
14. Enter the following command to view the log file path of the database instance:
15. Choose member from v$logfile.
16. The result will display a list of the log file paths for the database instance.

Before using these commands, make sure that the Oracle user has sufficient privileges to execute them.