diff --git a/src/Custom.php b/src/Custom.php
index b3ce240..fc1a068 100644
--- a/src/Custom.php
+++ b/src/Custom.php
@@ -26,7 +26,13 @@ class Custom
         $stmt  = $pdo->prepare($query);
         foreach ($parameters as $key => $value) {
             if ($debug) echo "<pre>Binding $value to $key\n</pre>";
-            $stmt->bindValue($key, $value);
+            $dataType = match (true) {
+                is_bool($value) => PDO::PARAM_BOOL,
+                is_int($value)  => PDO::PARAM_INT,
+                is_null($value) => PDO::PARAM_NULL,
+                default         => PDO::PARAM_STR
+            };
+            $stmt->bindValue($key, $value, $dataType);
         }
         if ($debug) echo '<pre>SQL: ' . $stmt->queryString . '</pre>';
         if ($stmt->execute()) return $stmt;
diff --git a/src/DocumentList.php b/src/DocumentList.php
index da5d0f3..60a7658 100644
--- a/src/DocumentList.php
+++ b/src/DocumentList.php
@@ -22,7 +22,7 @@ class DocumentList
      * @param PDOStatement|null $result The result of the query
      * @param Mapper<TDoc> $mapper The mapper to deserialize JSON
      */
-    private function __construct(private ?PDO $pdo, public ?PDOStatement $result, public Mapper $mapper) { }
+    private function __construct(private ?PDO $pdo, private ?PDOStatement $result, private Mapper $mapper) { }
 
     /**
      * Construct a new document list
@@ -46,17 +46,8 @@ class DocumentList
      */
     public function items(): Generator
     {
-        $debug = defined('PDO_DOC_DEBUG_SQL');
-        if ($debug) echo '*** CALLED GENERATOR ***';
-
         if ($this->result) {
-            if ($debug) echo 'There are results';
-            while ($row = $this->result->fetch(PDO::FETCH_ASSOC)) {
-                if ($debug) echo "<pre>Returning an item\n</pre>";
-                yield $this->mapper->map($row);
-            }
-        } else {
-            if ($debug) echo 'Nothing to return';
+            while ($row = $this->result->fetch(PDO::FETCH_ASSOC)) yield $this->mapper->map($row);
         }
         $this->result = null;
         $this->pdo    = null;