diff --git a/lib/DBD/SQLite/VirtualTable/PerlData.pm b/lib/DBD/SQLite/VirtualTable/PerlData.pm
index 697cd08..5af9977 100644
--- a/lib/DBD/SQLite/VirtualTable/PerlData.pm
+++ b/lib/DBD/SQLite/VirtualTable/PerlData.pm
@@ -115,7 +115,7 @@ sub BEST_INDEX {
           "($op($member))";
       } else {
         push @conditions,
-          "($op($member) && $op(\$vals[$ix]))";
+          "($op($member) && !defined(\$vals[$ix]))";
       }
     } elsif (SQLITE_3010000 && $op =~ /str/) {
       push @conditions,
diff --git a/t/virtual_table/rt_99748.t b/t/virtual_table/rt_99748.t
index 5315709..206680e 100644
--- a/t/virtual_table/rt_99748.t
+++ b/t/virtual_table/rt_99748.t
@@ -35,7 +35,7 @@ our $perl_rows = [
 ];
 
 my $tests = 14;
-$tests += 1 if has_sqlite('3.6.19');
+$tests += 2 if has_sqlite('3.6.19');
 plan tests => 4 + 2 * $tests + @interpolation_attempts + 9;
 
 my $dbh = connect_ok( RaiseError => 1, AutoCommit => 1 );
@@ -113,6 +113,10 @@ sub test_table {
     $sql = "SELECT a FROM $table WHERE c IS ?";
     $res = $dbh->selectcol_arrayref($sql, {}, undef);
     is_deeply $res, [7], $sql;
+
+    $sql = "SELECT a FROM $table WHERE c IS NOT ? order by a";
+    $res = $dbh->selectcol_arrayref($sql, {}, undef);
+    is_deeply $res, [1, 4, 10, 11, 12], $sql;
   }
 }