What to do after ORA-01658: unable to create INITIAL extent for segment in tablespace string?

Lately I've been getting into some troubles with free space in one of Oracle's table. The reason is that I didn't use option AUTOEXTEND when I created the table. If you use AUTOEXTEND option when a table is created, Oracle will extend the table when needed, but sometimes when you need to have more control on space usage don't use AUTOEXTEND option. The only way to get rid of that error is:

1. Clean up table - remove unneeded data

2. Manualy extend database

    ALTER DATABASE DATAFILE 'full_path_to_file' RESIZE 500M;



Thanks guys, I just about lost it lokonig for this.