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my $filter = "('Y' || 'N')";
my $sth = $dbh->prepare(q{SELECT name FROM catagories WHERE catagories
+.workrelated = ? ORDER BY name});
$sth->execute($filter);

my $sth = $dbh->prepare(q{SELECT name FROM catagories WHERE catagories
+.workrelated = ? ORDER BY name});
$sth->execute("('Y' || 'N')");

my $sth = $dbh->prepare(q{SELECT name FROM catagories WHERE catagories
+.workrelated = ('Y' || 'N') ORDER BY name});
$sth->execute();