WARNING: I could not determine Oracle client version so I'll just
default to version 8.0.0.0. Some features of DBD::Oracle may not work.
Oracle version based logic in Makefile.PL may produce erroneous result
+s.
You can use "perl Makefile.PL -V X.Y.Z" to specify a your client versi
+on.

Oracle version 8.0.0.0 (8.0)
DBD::Oracle no longer supports Oracle client versions before 9.2
Try a version before 1.25 for 9 and 1.18 for 8! at Makefile.PL line 27
+1.
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As previously discussed, you're going to have to stop ignoring the information displayed. This message is quite clear and the documentation discusses installation in detail.