Tài liệu Sybex OCA Oracle 10g Administration I Study Guide phần 4

If you are not using OMF, you will need to manage datafiles yourself. The database will create
or reuse one or more datafiles in the sizes and locations that you specify whenever you create a
tablespace. A datafile belongs to only one tablespace and only one database at a time. Temp files
are a special variety of datafile that are used in temporary tablespaces. When the database creates
or reuses a datafile, the operating system file is allocated and initialized—filled with a regular pattern
of mostly binary zeros. This initialization will not occur with temp files.