When encountering the error 58000: System error from Postgres DB, and assuming the role of a user without database administrator access, you should:
- Check the PostgreSQL Log Files: Immediately review the PostgreSQL log files for detailed error messages around the time the error occurred. This can often provide specific details about the cause of the system error. The location of these logs varies by installation but is typically found in the
pg_log directory within the data directory of your PostgreSQL installation. You can use the command: tail -n 100 /path/to/your/pg_log/logfile
- Replace
/path/to/your/pg_log/logfile with the actual path to your PostgreSQL log file to see the last 100 lines of the log. - Examine Running Processes and Locks: Sometimes, system errors can be due to long-running queries or locks that are holding up resources. You can check for any such issues with the following SQL commands:
- To see currently running queries:
SELECT pid, age(clock_timestamp(), query_start), usename, query
FROM pg_stat_activity
WHERE state = 'active';
- To check for locks:
SELECT pid, relation::regclass, mode, granted
FROM pg_locks l
JOIN pg_stat_activity a ON l.pid = a.pid
WHERE NOT granted;
- Check Disk Space: A common cause for system errors can be insufficient disk space. Use the command:
df -h
- This shows the available disk space on all mounted filesystems. Make sure there's sufficient free space, especially in the directory where PostgreSQL stores its data.
- Review System Resources: Check if the PostgreSQL server is running out of memory or if there's high CPU usage, which could also lead to system errors. Use commands like:
- For memory usage:
free -m
- For CPU usage:
top
- Restart PostgreSQL Service: If the issue is not resolved by the above steps and it's feasible (i.e., it won't disrupt critical operations), try restarting the PostgreSQL service. This can sometimes clear up issues that are causing system errors. Use the command:
sudo systemctl restart postgresql
- Or, depending on your system setup, the command might vary (e.g.,
sudo service postgresql restart for older systems).
Remember, these are immediate actions. After taking these steps, you should consider investigating the root cause more deeply, possibly involving a database specialist if the issue persists or recurs.
