Quoting '?' placeholder in Perl's DBD::Pg?

Hi anyone know how I can quote or turn off the ? placeholder in Perl's
DBD::Pg?

I've asked on the perl modules newsgroups but I didn't get any satisfactory
answer.

Say I'm constructing a custom SQL query and it turns out that there is a ?
somewhere, how do I quote it out? It gets recognised as a placeholder by
the DBD::Pg driver.
e.g.
my $SQL=<<"EOT";
insert into blah (a,b) values ('asdad?rerwe','blah')
EOT

The ? gets interpreted as a placeholder.

Sure I can do
my $SQL=<<"EOT";
insert into blah (a,b) values (?,?)
EOT

And do the execute thing. But if the number of columns changes from query
to query, and so on it might be less convenient to use placeholders.

If it really can't be done, then yeah I'll use placeholders. But it seems
strange if you can't.

Cheerio,
Link.