How to clean up a full Oracle database disk?

When the Oracle database disk is full, you can take the following steps to clean up:

1. Find large files: Utilize operating system commands or tools such as the du command or file explorer to locate files within the database directory that are taking up a large amount of space. You can delete any unnecessary backup files, log files, or temporary files.
2. Clearing log files: Use the ARCHIVE LOG LIST command to view the directory of archived logs and delete some outdated archived log files. You can use the RMAN command to delete archived logs.
3. Cleaning up temporary tablespace: The temporary files in the TEMP tablespace may consume a large amount of disk space. You may want to consider reducing the size of the TEMP tablespace or recreating the temporary tablespace.
4. Clean up table data: Release space by deleting some unnecessary data rows. You can use the DELETE statement to delete data, or the TRUNCATE statement to delete all data from the table.
5. Compression of tables and indexes can reduce disk space usage. You can compress a table using the COMPRESS option in the ALTER TABLE statement, or rebuild an index using the REBUILD option in the ALTER INDEX statement.
6. Moving table spaces: If there are multiple table spaces, consider moving some of the larger tables to a table space with more space to free up space in the original table space.
7. Increase disk space: If the previous steps do not resolve the issue of a full disk space, consider increasing the disk space by adding a new physical disk or expanding the existing physical disk.

Before carrying out the steps mentioned above, it is recommended to back up the database to prevent data loss. Additionally, the cleaning process should be done carefully to ensure that important data or files are not deleted. If unsure how to proceed with the cleaning process, it is advisable to seek assistance from a database administrator or professional.