How to find the ORACLE_HOME path in Oracle Database?

In 9i:

SELECT substr(file_spec,1,instr(file_spec,'lib')-2) ORACLE_HOME FROM dba_libraries
WHERE library_name='DBMS_SUMADV_LIB';

In 10g:

SQL > var OHM varchar2(100);
SQL > EXEC dbms_system.get_env('ORACLE_HOME', :OHM) ;
SQL > PRINT OHM

Linux/Unix:

echo $ORACLE_HOME

Windows:

start - run - regedit (enter) - HKEY_LOCAL_MACHINE - SOFTWARE - ORACLE

Type the below command at prompt if the environment variable is defined for ORACLE_HOME

c:\> set oracle_home (ENTER)

Update: Take a look at my other post on "Setting an Oracle Environment variable – ORACLE_HOME"

My blog has been added in Oracle Blogs list !!

Dear Friend,

This is to inform you that my blog http://sabdarsyed.blogspot.com has been reviewed by Oracle and added in Oracle’s official web site http://blogs.oracle.com/ where all most all top blogs, on Oracle Technology, have been registered.

Happy Reading !!

With Best Regards,

Sabdar Syed,

Received My Oracle 11i Apps DBA Certification yesterday !!

Dear Friends,

This is to tell you that, I have received my “Oracle E-Business Suite 11i Certification” right after one month as I took the “1Z0-233 - Oracle 11i Install, Patch and Maintain Applications” last month. It’s titled in that as “Oracle E-Business Suite 11i Applications Database Administration Certified Professional”

Refer my blog for the exam details i.e. “1Z0-233 - Oracle 11i Install, Patch and Maintain Applications”

http://sabdarsyed.blogspot.com/2007/07/i-have-passed-1z0-233-exam-oracle-11i.html

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Best Regards,
Sabdar Syed,

http://sabdarsyed.blogspot.com