Files managed by OMF are automatically deleted.

Files managed by OMF will be automatically deleted by experienced DBAs. When you drop tablespace, data files will not be deleted without the words including contents and datafiles, during the demonstration on Sunday last week, when you drop tablespace, the data file was automatically deleted. At that time, I explained that the file was empty and never used before, this is because the file is OMF. 01 [oracle @ nobody admin] $ rlwrap sqlplus/as sysdba02 03SQL * Plus: Release 11.2.0.1.0 Production on Mon Jun 24 05:44:20 201304 05 Copyright (c) 1982,200 9, Oracle. all rights reserved.06 07 08 Connected to: 09 Oracle Database 11g Enterprise Edition Release 11.2.0.1.0-64bit Production10With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP, 11 Data Mining and Real Applicati On Testing options12 13nobody @ TESTDB> show parameter create; 14 15 name type VALUE16 certificate ----------- listen 17create_bitmap_area_size integer comment string19db_create_file_dest string + Comment comment exceed limit T_4 character string25nobody @ TESTDB> alter system set db_create_file_dest = '/u01/app/oracle/oradata/testdb'; 26 27 System altered.28 29nobody @ testdb> create tablespace omf_tbs datafile size 10 m; 30 31 Tablespace created.32 33nobody @ TESTDB> create tablespace no_omf_tbs datafile '/u01/app/oracle/oradata/testdb/comment 'size 10 m; 34 35 Tablespace created.36 37nobody @ TESTDB> se Lect d. name from v $ datafile d, v $ tablespace t where d. ts # = t. ts # and t. name in ('omf _ TBS ', 'no _ OMF_TBS'); 38 rows/u01/app/oracle/oradata/testdb/201701/datafile/o1_mf_omf_tbs_8wgv3shj _. dbf42/u01/app/oracle/oradata/testdb/no_omf_tbs01.dbf43 44nobody @ TESTDB> h Ost ls-l/u01/app/oracle/oradata/testdb/000001/datafile/o1_mf_omf_tbs_8wgv3shj _. dbf45-rw-r ----- 1 oracle asmadmin 10493952 Jun 24/u01/app/oracle/oradata/testdb/201701/datafile/o1_mf_omf_tbs_8wgv3shj _. dbf46 47nobody @ TESTDB> host ls-l/u01/app/oracle/oradata/testdb/no_omf_tbs01.dbf48-rw-r ----- 1 oracle asmadmin 10493952 Jun 24/u01/app/oracle/oradata/testdb/ no_omf_tbs01.dbf49 50nobody @ TE STDB> drop tablespace omf_tbs; 51 52 Tablespace dropped.53 54nobody @ TESTDB> host ls-l/u01/app/oracle/oradata/testdb/201701/datafile/o1_mf_omf_tbs_8wgv3shj _. dbf55ls:/u01/app/oracle/oradata/testdb/000001/datafile/o1_mf_omf_tbs_8wgv3shj _. dbf: No such file or directory56 57nobody @ TESTDB> drop tablespace no_omf_tbs; 58 59 Tablespace dropped.60 61nobody @ TESTDB> host ls-l/u01/app/oracle/oradata/testdb/no_omf _ Tbs01.dbf62-rw-r ----- 1 oracle asmadmin 10493952 Jun 24/u01/app/oracle/oradata/testdb/no_omf_tbs01.dbfPerformance Tuning Guide. When file systems can contain all Oracle Database data, database administration is simplified by using Oracle Managed Files. oracle Database internally uses standard file system interfaces to create and delete files as needed for tablespaces, temp files, online logs, and control files. administrators only specify the file system directory to be used for a participant type of file. you can specify one default location for data files and up to five multiplexed locations for the control and online redo log files. oracle Database ensures that a unique file is created and then deleted when it is no longer needed. this vulnerability CES caused uption caused by administrators specifying the wrong file, CES wasted disk space consumed by obsolete files, and simplifies creation of test and development databases.