diff --git a/UPGRADE.md b/UPGRADE.md
index 9b32247..6025cc0 100644
--- a/UPGRADE.md
+++ b/UPGRADE.md
@@ -4,6 +4,7 @@
 
 ### Global Changes
 - Recommended folder structure by symfony adopted
+- [IMPROVEMENT] Use Generator to index data which will increase processing speed significant
 
 ***
 
diff --git a/src/Service/Builder/AssetListBuilder.php b/src/Service/Builder/AssetListBuilder.php
index 6efd0bd..b5a6a6b 100644
--- a/src/Service/Builder/AssetListBuilder.php
+++ b/src/Service/Builder/AssetListBuilder.php
@@ -17,11 +17,15 @@ public function __construct(
     ) {
     }
 
-    public function buildByList(array $options): array
+    public function buildByList(array $options): \Generator
     {
         $list = $this->getList($options);
 
-        return $list->getAssets();
+        foreach ($list->loadIdList() as $id) {
+            if ($asset = Asset::getById($id)) {
+                yield $asset;
+            }
+        }
     }
 
     public function buildByIdList(int $id, array $options): ?ElementInterface
@@ -33,10 +37,6 @@ public function buildByIdList(int $id, array $options): ?ElementInterface
 
         $assets = $list->getAssets();
 
-        if (!is_array($assets)) {
-            return null;
-        }
-
         if (count($assets) === 0) {
             return null;
         }
diff --git a/src/Service/Builder/DataBuilderInterface.php b/src/Service/Builder/DataBuilderInterface.php
index 09877a2..06d1105 100644
--- a/src/Service/Builder/DataBuilderInterface.php
+++ b/src/Service/Builder/DataBuilderInterface.php
@@ -6,7 +6,7 @@
 
 interface DataBuilderInterface
 {
-    public function buildByList(array $options): array;
+    public function buildByList(array $options): \Generator;
 
     public function buildByIdList(int $id, array $options): ?ElementInterface;
 
diff --git a/src/Service/Builder/DocumentListBuilder.php b/src/Service/Builder/DocumentListBuilder.php
index 96e3fcf..7c23683 100644
--- a/src/Service/Builder/DocumentListBuilder.php
+++ b/src/Service/Builder/DocumentListBuilder.php
@@ -18,11 +18,15 @@ public function __construct(
     ) {
     }
 
-    public function buildByList(array $options): array
+    public function buildByList(array $options): \Generator
     {
         $list = $this->getList($options);
 
-        return $list->getDocuments();
+        foreach ($list->loadIdList() as $id) {
+            if ($doc = Document::getById($id)) {
+                yield $doc;
+            }
+        }
     }
 
     public function buildByIdList(int $id, array $options): ?ElementInterface
@@ -34,10 +38,6 @@ public function buildByIdList(int $id, array $options): ?ElementInterface
 
         $documents = $list->getDocuments();
 
-        if (!is_array($documents)) {
-            return null;
-        }
-
         if (count($documents) === 0) {
             return null;
         }
diff --git a/src/Service/Builder/ObjectListBuilder.php b/src/Service/Builder/ObjectListBuilder.php
index 47095ab..2a7af7c 100644
--- a/src/Service/Builder/ObjectListBuilder.php
+++ b/src/Service/Builder/ObjectListBuilder.php
@@ -17,11 +17,15 @@ public function __construct(
     ) {
     }
 
-    public function buildByList(array $options): array
+    public function buildByList(array $options): \Generator
     {
         $list = $this->getList($options);
 
-        return $list->getObjects();
+        foreach ($list->loadIdList() as $id) {
+            if ($object = DataObject::getById($id)) {
+                yield $object;
+            }
+        }
     }
 
     public function buildByIdList(int $id, array $options): ?ElementInterface
@@ -33,10 +37,6 @@ public function buildByIdList(int $id, array $options): ?ElementInterface
 
         $objects = $list->getObjects();
 
-        if (!is_array($objects)) {
-            return null;
-        }
-
         if (count($objects) === 0) {
             return null;
         }
diff --git a/src/Service/DataProviderService.php b/src/Service/DataProviderService.php
index 2bd30af..4df33b4 100644
--- a/src/Service/DataProviderService.php
+++ b/src/Service/DataProviderService.php
@@ -136,7 +136,9 @@ protected function fetchByTypeAndId(string $type, string $providerBehaviour, int
 
         $element = $builder->buildById($id);
 
-        $this->dispatchData([$element], $providerBehaviour, $resourceMeta);
+        if ($element instanceof ElementInterface) {
+            $this->dispatchElement($element, $providerBehaviour, $resourceMeta);
+        }
     }
 
     protected function log(string $level, string $message): void
@@ -144,16 +146,21 @@ protected function log(string $level, string $message): void
         $this->logger->log($level, $message, DsTrinityDataBundle::PROVIDER_NAME, $this->contextName);
     }
 
-    protected function dispatchData(array $elements, string $providerBehaviour, ?ResourceMetaInterface $resourceMeta = null): void
+    protected function dispatchData(\Generator $elements, string $providerBehaviour, ?ResourceMetaInterface $resourceMeta = null): void
     {
         foreach ($elements as $element) {
-            $newDataEvent = new NewDataEvent($this->contextDispatchType, $this->contextName, $element, $providerBehaviour, $resourceMeta);
-            $this->eventDispatcher->dispatch($newDataEvent, DynamicSearchEvents::NEW_DATA_AVAILABLE);
-
-            $this->dispatchProcessControlSignal();
+            $this->dispatchElement($element, $providerBehaviour, $resourceMeta);
         }
     }
 
+    protected function dispatchElement(ElementInterface $element, string $providerBehaviour, ?ResourceMetaInterface $resourceMeta = null): void
+    {
+        $newDataEvent = new NewDataEvent($this->contextDispatchType, $this->contextName, $element, $providerBehaviour, $resourceMeta);
+        $this->eventDispatcher->dispatch($newDataEvent, DynamicSearchEvents::NEW_DATA_AVAILABLE);
+
+        $this->dispatchProcessControlSignal();
+    }
+
     protected function addSignalListener(): void
     {
         if (php_sapi_name() !== 'cli') {