diff --git a/src/Entity/Field/Date.php b/src/Entity/Field/Date.php
index c2c5e7e..8724cd3 100644
--- a/src/Entity/Field/Date.php
+++ b/src/Entity/Field/Date.php
@@ -5,9 +5,4 @@ namespace Ulmus\Entity\Field;
 class Date extends Datetime {
     
     public string $format = "Y-m-d";
-    
-    public function formatLocale(string $format) : string
-    {
-        return strftime($format, $this->getTimestamp());
-    }
 }
diff --git a/src/EntityCollection.php b/src/EntityCollection.php
index 478058b..cb17ff8 100644
--- a/src/EntityCollection.php
+++ b/src/EntityCollection.php
@@ -44,6 +44,15 @@ class EntityCollection extends \ArrayObject {
         }
     }
 
+    public function filtersOne(Callable $callback) : ? object
+    {
+        foreach($this->filters($callback, true) as $item) {
+            return $item;
+        }
+
+        return null;
+    }
+
     public function iterate(Callable $callback) : self
     {
         foreach($this as $item) {
@@ -290,6 +299,20 @@ class EntityCollection extends \ArrayObject {
         return $this;
     }
 
+    public function batch(int $size, $fill = null, $preserveKeys = true) : array
+    {
+        $batch = [];
+        $split = ceil( $this->count() / $size );
+
+        for($i = 0; $i < $split; $i++) {
+            $slice = array_slice($this->getArrayCopy(), $i * $size, $size, $preserveKeys);
+            $pad = ( count($slice) !== $size ) && ( $fill !== null );
+            $batch[] = $pad ? array_pad($slice, $size, $fill) : $slice;
+        }
+
+        return $batch;
+    }
+
     public function randomize() : self
     {
         $arr = $this->getArrayCopy();
@@ -313,6 +336,16 @@ class EntityCollection extends \ArrayObject {
         return $this->reverse();
     }
 
+    public function sortField(? string $field = null) : self
+    {
+        return $this->sort(fn($e1, $e2) => $field ? $e1->$field <=> $e2->$field : $e1 <=> $e2);
+    }
+
+    public function rsortField(string $field) : self
+    {
+        return $this->sort(fn($e1, $e2) => $field ? $e2->$field <=> $e1->$field : $e2 <=> $e1);
+    }
+
     public function reverse() : self
     {
         return $this->replaceWith(array_reverse($this->getArrayCopy()));;
diff --git a/src/Exception/InvalidFieldType.php b/src/Exception/InvalidFieldType.php
new file mode 100644
index 0000000..6888726
--- /dev/null
+++ b/src/Exception/InvalidFieldType.php
@@ -0,0 +1,5 @@
+<?php
+
+namespace Ulmus\Exception;
+
+class InvalidFieldType extends \Exception {}
diff --git a/src/Query/Fragment.php b/src/Query/Fragment.php
index 5b83a6b..e8bc199 100644
--- a/src/Query/Fragment.php
+++ b/src/Query/Fragment.php
@@ -28,4 +28,11 @@ abstract class Fragment {
 
         return implode(", ", $list);
     }
+
+    protected function validateFieldType($field) : void
+    {
+        if ( is_numeric($field) ) {
+            throw new \Ulmus\Exception\InvalidFieldType(sprintf("Validation of field `%s` failed from query `%s`", $field, get_class($this)));
+        }
+    }
 }
diff --git a/src/Query/GroupBy.php b/src/Query/GroupBy.php
index feb81b0..f1d31f9 100644
--- a/src/Query/GroupBy.php
+++ b/src/Query/GroupBy.php
@@ -18,6 +18,8 @@ class GroupBy extends Fragment {
 
     public function add(string $field) : self
     {
+        $this->validateFieldType($field);
+
         $this->groupBy[] = $field;
         
         return $this;
diff --git a/src/Query/Having.php b/src/Query/Having.php
index a106e99..96552bd 100644
--- a/src/Query/Having.php
+++ b/src/Query/Having.php
@@ -29,6 +29,9 @@ class Having extends Fragment {
 
     public function add($field, $value, string $operator, string $condition, bool $not = false) : self
     {
+        $this->validateFieldType($field);
+        # $this->validateValueType($value);
+
         $this->conditionList[] = [
             $field,
             $value,
@@ -102,7 +105,8 @@ class Having extends Fragment {
                     return (in_array($this->operator, [ '!=', '<>' ]) ? Where::CONDITION_NOT . " " : "") . Where::COMPARISON_IN;
                 }
 
-                return $this->operator;
+                # whitelisting operators
+                return in_array(strtoupper($this->operator), [ '=', '!=', '<>', 'LIKE' ]) ? $this->operator : "=";
             }
 
             protected function value()
@@ -124,6 +128,7 @@ class Having extends Fragment {
             {
                 if ( $value === null ) {
                     $this->operator = in_array($this->operator, [ '!=', '<>' ]) ? Where::COMPARISON_IS . " " . Where::CONDITION_NOT : Where::COMPARISON_IS;
+
                     return Where::COMPARISON_NULL;
                 }
                 elseif ( is_object($value) && ( $value instanceof EntityField ) ) {
diff --git a/src/Query/Like.php b/src/Query/Like.php
deleted file mode 100644
index 917d780..0000000
--- a/src/Query/Like.php
+++ /dev/null
@@ -1,7 +0,0 @@
-<?php
-
-namespace Ulmus\Query;
-
-class Like extends Fragment {
-
-}
diff --git a/src/Query/OrderBy.php b/src/Query/OrderBy.php
index 318690a..bb971ed 100644
--- a/src/Query/OrderBy.php
+++ b/src/Query/OrderBy.php
@@ -18,6 +18,8 @@ class OrderBy extends Fragment {
 
     public function add(string $field, ? string $direction = null) : self
     {
+        $this->validateFieldType($field);
+
         $this->orderBy[] = [ $field, $direction ];
         
         return $this;
diff --git a/src/Query/Where.php b/src/Query/Where.php
index d1db936..72e7b17 100644
--- a/src/Query/Where.php
+++ b/src/Query/Where.php
@@ -37,6 +37,9 @@ class Where extends Fragment {
     
     public function add($field, $value, string $operator, string $condition, bool $not = false) : self
     {
+        $this->validateFieldType($field);
+        # $this->validateValueType($value);
+
         $this->conditionList[] = [
             $field,
             $value,
@@ -110,7 +113,8 @@ class Where extends Fragment {
                     return (in_array($this->operator, [ '!=', '<>' ]) ? Where::CONDITION_NOT . " " : "") . Where::COMPARISON_IN;
                 }
 
-                return $this->operator;
+                # whitelisting operators
+                return in_array(strtoupper($this->operator), [ '=', '!=', '<>', 'LIKE' ]) ? $this->operator : "=";
             }
 
             protected function value()
diff --git a/src/QueryBuilder.php b/src/QueryBuilder.php
index ec78463..7d30901 100644
--- a/src/QueryBuilder.php
+++ b/src/QueryBuilder.php
@@ -48,7 +48,7 @@ class QueryBuilder implements Query\QueryBuilderInterface
         }
     }
     
-    public function select($field) : self
+    public function select($field, bool $distinct = false) : self
     {
         if ( null !== ( $select = $this->getFragment(Query\Select::class) ) ) {
             $select->add($field);
@@ -59,6 +59,8 @@ class QueryBuilder implements Query\QueryBuilderInterface
             $this->push($select);
         }
 
+        $select->distinct = $distinct;
+
         return $this;
     }
     
@@ -401,7 +403,7 @@ class QueryBuilder implements Query\QueryBuilderInterface
     public function getFragment(string $class, int $index = 0) : ? Query\Fragment
     {
         foreach($this->queryStack as $item) {
-            if ( get_class($item) === $class ) {
+            if ( is_a($item, $class, true) ) {
                 if ( $index-- === 0 ) {
                     return $item;
                 }
@@ -419,6 +421,11 @@ class QueryBuilder implements Query\QueryBuilderInterface
             }
         }
     }
+
+    public function getFragments() : array
+    {
+        return $this->queryStack;
+    }
     
     public function __toString() : string
     {
diff --git a/src/Repository.php b/src/Repository.php
index 05c0f31..00ab211 100644
--- a/src/Repository.php
+++ b/src/Repository.php
@@ -31,7 +31,7 @@ class Repository
         $this->queryBuilder = new QueryBuilder();
     }
     
-    public function __clone() 
+    public function __clone()
     {
         #$this->queryBuilder = clone $this->queryBuilder;
     }
@@ -285,6 +285,8 @@ class Repository
                 $this->select("$alias.$key as {$prependField}{$field['name']}");
             }
         }
+
+        return $this;
     }
 
     public function selectJsonEntity(string $entity, string $alias, bool $skipFrom = false) : self
@@ -307,9 +309,9 @@ class Repository
         );
     }
 
-    public function select(/*array|Stringable*/ $fields) : self
+    public function select(/*array|Stringable*/ $fields, bool $distinct = false) : self
     {
-        $this->queryBuilder->select($fields);
+        $this->queryBuilder->select($fields, $distinct);
 
         return $this;
     }
@@ -616,7 +618,7 @@ class Repository
     public function filterServerRequest(SearchRequest\SearchRequestInterface $searchRequest, bool $count = true) : self
     {
         if ($count) {
-            $searchRequest->count = $searchRequest->filter(new Repository\ServerRequestCountRepository($this->entityClass, $this->alias, $this->adapter))
+            $searchRequest->count = $searchRequest->filter($this->serverRequestCountRepository())
                 ->wheres($searchRequest->wheres(), Query\Where::OPERATOR_EQUAL, Query\Where::CONDITION_AND)
                 ->likes($searchRequest->likes(), Query\Where::CONDITION_OR)
                 ->groups($searchRequest->groups())
@@ -632,6 +634,11 @@ class Repository
             ->limit($searchRequest->limit());
     }
 
+    protected function serverRequestCountRepository() : Repository
+    {
+        return new Repository\ServerRequestCountRepository($this->entityClass, $this->alias, $this->adapter);
+    }
+
     public function collectionFromQuery(? string $entityClass = null) : EntityCollection
     {
         $class = $entityClass ?: $this->entityClass;
@@ -646,7 +653,7 @@ class Repository
             $entityCollection->append( ( new $class() )->resetVirtualProperties()->entityFillFromDataset($entityData) );
         }
 
-        $this->eventExecute(Event\RepositoryCollectionFromQueryInterface::class, $entityCollection);
+        $this->eventExecute(Event\Repository\CollectionFromQueryInterface::class, $entityCollection);
 
         return $entityCollection;
     }
@@ -793,6 +800,11 @@ class Repository
         return $this->adapter->adapter()->escapeIdentifier($identifier, Adapter\AdapterInterface::IDENTIFIER_SCHEMA);
     }
 
+    public function hasFilters() : bool
+    {
+        return isset($this->queryBuilder->where);
+    }
+
     protected function matchEntity(object $entity) {
         return get_class($entity) === $this->entityClass;
     }
diff --git a/src/Repository/MssqlRepository.php b/src/Repository/MssqlRepository.php
index e1d1741..590fb47 100644
--- a/src/Repository/MssqlRepository.php
+++ b/src/Repository/MssqlRepository.php
@@ -7,7 +7,7 @@ use Ulmus\{ Repository, Query };
 class MssqlRepository extends Repository {
 
     protected function finalizeQuery() : void
-    { 
+    {
         if ( null !== $offset = $this->queryBuilder->getFragment(Query\Offset::class) ) {
             if ( null === $limit = $this->queryBuilder->getFragment(Query\Limit::class) ) {
                 throw new \Exception("Your offset query fragment is missing a LIMIT value.");
@@ -28,6 +28,7 @@ class MssqlRepository extends Repository {
             $this->queryBuilder->push($mssqlOffset);
         }
         elseif ( null !== $limit = $this->queryBuilder->getFragment(Query\Limit::class) ) {
+
             if ( null !== $select = $this->queryBuilder->getFragment(Query\Select::class) ) {
                 $select->top = $limit->limit;
             }
diff --git a/src/SearchRequest/SearchRequestConstructorTrait.php b/src/SearchRequest/SearchRequestConstructorTrait.php
new file mode 100644
index 0000000..db02cbf
--- /dev/null
+++ b/src/SearchRequest/SearchRequestConstructorTrait.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace Ulmus\SearchRequest;
+
+use Psr\Http\Message\ServerRequestInterface;
+
+trait SearchRequestConstructorTrait
+{
+    public function __construct(array $parameters = [])
+    {
+        $this->fromArray($parameters);
+    }
+
+    public function fromArray(array $data): self
+    {
+        foreach(array_filter($data, fn($e) => $e !== "") as $key => $value) {
+            $this->$key = $value;
+        }
+
+        return $this;
+    }
+}
\ No newline at end of file