ORACLE Database Space Organization experience

Recently, due to insufficient hard disk space in the unit database, I checked many articles and tested them. I learned some experiences for your reference.

First, I saw an article on the internet, how to Shrink Undo tablespaces and release space that is overoccupied. I used the following command to read it, we found that the UNDO space on our hard disk also occupied 2 GB, so we thought of clearing the space first to solve the urgent problem, so we immediately conducted a test.

The test passed, but there was a problem: the drop tablespace undotbs1 including contents command above did not clear the undotbs1.dbf file, and the hard disk was full. (Later I thought, could I use drop tablespace undotbs1 including contents and datafiles? Simply delete the files on the hard disk .) As mentioned in the article, I have to wait for all undo SEGMENT offlines in the original UNDO tablespace. I don't know how to operate this table, nor can I understand the results of the preceding commands. However, run the command to check whether the UNDO tablespace has been transferred to undotbs2.

In order to delete the UNDO file, a test was conducted.

Selecct name from v $ datafile; this undotbs1.dbf file is no longer available in the listed data files.

Stop the ORACLE service and stop listening. Move the undotbs1.dbf file to another space. Open the ORACLE service and enable the listener. The service is normal. This file can be deleted.