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How to obtain Information about Database Files using Oracle

Oracle Database Files Concepts

The final components of the Oracle architecture are the physical files where our information resided on disk. Oracle has several types for data files, two of the five listed are described below.
  1. Database datafiles
  2. Control files
  3. Online redo logs
  4. Parameter files
  5. Other database related files

Database datafiles

Database datafiles are physical files stored on disk and these files are used to store data on disk. Database datafiles are only written to by the DBWR processes.
These database datafiles are associated with Oracle tablespaces, which are logical containers for tables and indexes.

Control files

The Control File of the database is a binary file that contains a great deal of database information. The control file contains the
  1. database name and
  2. data about the database log files.
Oracle cannot function without valid control files.
Because the control file is so important, Oracle allows you to maintain duplicate copies of the control file. When you have more than one control file, then you are said to be multiplexing your control files. It is a good practice to put these multiple copies on different disks to protect the control file.

How to obtain information about database files

To get a list of names and the status of all datafiles from V$DATAFILE in SQL*PLUS, the DBA issues a SELECT statement.

To find all the control files, a DBA can use the V$CONTROLFILE view

The DBA can use the V$LOGFILE view to find the names of all redo log files. Note the correct column in the select statement is MEMBER for this view.

The DBA can use the DBA_DATA_FILES data dictionary view to get a list of all datafiles and their respective tablespaces