It is also important to handle the pipes properly with wait to avoid creating zombies. Here is an example that enables an external middleware program called ac_bl to be the basis of a general SQL subroutine.

use IPC::Open2;
use POSIX ":sys_wait_h";

my @results = Sql( 'select ...' );

sub Sql {
    my $command = shift;
    my $options = ( shift() || '-qs' ) . ' -';
    my $pid = open2 my $rh, my $wh, 'ac_bl ' . $options;
    write $wh $command;
    close $wh;
    my @results = <$rh>;
    chop @results;
    close $rh;
    waitpid $pid, 0;
    return @results;
}
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Update: Although if this weren't a one-off I'd create a class for this with a 'fetch' method that uses wantarray to distinguish between a call that wants the lot and one that wants to fetch only one line of result output at a time.