IPC::Run provides an easy solution. 
use strict;
use warnings;

use IPC::Run qw( run );

my @cmd = qw( sqlplus.exe -s scott/tiger@butthead );

my $in = <<'__END_OF_SQL__';
set echo off
set lines 1000
set trims on
set serverout on size 999999
set feed off
exec dbms_output.put_line('Hello There');
exit;
__END_OF_SQL__

run \@cmd, \$in, \my $out;

print $out;

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In reply to Re: Question: Redirection of stdout to scalar variable by ikegami
in thread Question: Redirection of stdout to scalar variable by jujiro_eb

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