The documentation tells you. See http://search.cpan.org/~timb/DBD-Oracle-1.15/Oracle.pm
The ORACLE_HOME environment variable should be set correctly. In general, the value used should match the version of Oracle that was used to build DBD::Oracle. If using dynamic linking then ORACLE_HOME should match the version of Oracle that will be used to load in the Oracle client libraries (via LD_LIBRARY_PATH, ldconfig, or similar on Unix).
Followed by example 
$ENV{ORACLE_HOME} = '/home/oracle/product/7.x.x';

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Get it now?

In reply to Re^3: What are DBD::Oracle's dependencies (on Linux)? by Anonymous Monk
in thread What are DBD::Oracle's dependencies (on Linux)? by nguye103

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