turnstep's advice above should always be your first step in diagnosing DBI issues. There is no reason why what you are describing should not work (aside from the spurious HTML tags). If SQL queries with spaces in them did not work, we would all have some serious problems. Likewise with bound values.

my $looking_for = 'some string with spaces';
my $sth = $dbh->prepare('select field from table where key=?');
$sth->execute($looking_for);
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There is 0 reason why this should not work, especially if you're doing it against DBD::Oracle. I do stuff like this every day without a problem. Try adding some additional error checking and see if that doesn't help you locate your problem.