When using any RDBMS there exist a distinct difference between the actual size of the data and the physical size of the database. In this article we will demonstrate how to get the actual size of the data stored in an Oracle RDBMS.
1. Logon to your Oracle database server as the Oracle software owner.
2. Logon to SQLPLUS with SYSDBA privileges.
mylinux:> sqlplus ‘/ as sysdba’
SQL*Plus: Release 10.2.0.4.0 – Production on Mon Mar 01 17:17:02 2010
Copyright (c) 1982, 2007, Oracle. All Rights Reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 – 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL>
3. Select the sum of all bytes allocated in the view DBA_SEGMENTS, returns the actual space being consumed on disk.
SQL> select sum(bytes)/1024/1024 from dba_segments;
SUM(BYTES)/1024/1024
——————–
316865.805
4. This completes the determining the actual size of data in an Oracle database.
Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com