I would like to timeout this statement after about 15 secs

You want to set an alarm for 15 seconds, and attempt the connection in an eval block.

my $db;

eval {
   local $SIG{ALRM} = sub { die "connect timeout\n" };
   alarm 15;
   $db = DBI->connect("DBI:Oracle:".... ) or die $DBI::errstr;
   alarm 0;
};

if ($@) {
   # timed out
   die unless $@ eq "connect timeout\n";
}
elsif (!$db) {
   # didn't connect
   die "no database connection\n";
}

# $db is ok here
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If you're running on Win32, I believe you're out of luck, because alarm isn't implemented. Or it could be that it is now implemented in 5.8.8 and/or there's another technique that taps Win32::API to achieve the same functionality.

update: it looks like alarm is implemented in Active Perl build 819 (version 5.8.8) at least (don't know which exact version introduced this).

H:\>perl -wle "eval {$SIG{ALRM}=sub{die qq{ook\n}}; alarm(3); 1 while 
+1; alarm(0)}; print
$@"
ook
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