diff --git a/src/BaseCollection.php b/src/BaseCollection.php
index 8bad3b8d2..4d5803d58 100644
--- a/src/BaseCollection.php
+++ b/src/BaseCollection.php
@@ -28,6 +28,30 @@ abstract class BaseCollection extends \ArrayIterator
 		$this->totalCount = $totalCount ?? count($models);
 	}
 
+	/**
+	 * @inheritDoc
+	 */
+	public function offsetSet($offset, $value)
+	{
+		if (is_null($offset)) {
+			$this->totalCount++;
+		}
+
+		parent::offsetSet($offset, $value);
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function offsetUnset($offset)
+	{
+		if ($this->offsetExists($offset)) {
+			$this->totalCount--;
+		}
+
+		parent::offsetUnset($offset);
+	}
+
 	/**
 	 * @return int
 	 */
@@ -35,4 +59,42 @@ abstract class BaseCollection extends \ArrayIterator
 	{
 		return $this->totalCount;
 	}
+
+	/**
+	 * Return the values from a single field in the collection
+	 *
+	 * @param string   $column
+	 * @param int|null $index_key
+	 * @return array
+	 * @see array_column()
+	 */
+	public function column($column, $index_key = null)
+	{
+		return array_column($this->getArrayCopy(), $column, $index_key);
+	}
+
+	/**
+	 * Apply a callback function on all elements in the collection and returns a new collection with the updated elements
+	 *
+	 * @param callable $callback
+	 * @return BaseCollection
+	 * @see array_map()
+	 */
+	public function map(callable $callback)
+	{
+		return new static(array_map($callback, $this->getArrayCopy()), $this->getTotalCount());
+	}
+
+	/**
+	 * Filters the collection based on a callback that returns a boolean whether the current item should be kept.
+	 *
+	 * @param callable|null $callback
+	 * @param int           $flag
+	 * @return BaseCollection
+	 * @see array_filter()
+	 */
+	public function filter(callable $callback = null, int $flag = 0)
+	{
+		return new static(array_filter($this->getArrayCopy(), $callback, $flag));
+	}
 }
diff --git a/src/BaseModel.php b/src/BaseModel.php
index 5a2708914..b2dc7eeda 100644
--- a/src/BaseModel.php
+++ b/src/BaseModel.php
@@ -69,6 +69,18 @@ abstract class BaseModel
 		return $model;
 	}
 
+	/**
+	 * Magic isset method. Returns true if the field exists, either in the data prperty array or in any of the local properties.
+	 * Used by array_column() on an array of objects.
+	 *
+	 * @param $name
+	 * @return bool
+	 */
+	public function __isset($name)
+	{
+		return in_array($name, array_merge(array_keys($this->data), array_keys(get_object_vars($this))));
+	}
+
 	/**
 	 * Magic getter. This allows to retrieve model fields with the following syntax:
 	 * - $model->field (outside of class)
@@ -80,9 +92,7 @@ abstract class BaseModel
 	 */
 	public function __get($name)
 	{
-		if (empty($this->data['id'])) {
-			throw new HTTPException\InternalServerErrorException(static::class . ' record uninitialized');
-		}
+		$this->checkValid();
 
 		if (!array_key_exists($name, $this->data)) {
 			throw new HTTPException\InternalServerErrorException('Field ' . $name . ' not found in ' . static::class);
@@ -104,4 +114,11 @@ abstract class BaseModel
 	{
 		return $this->data;
 	}
+
+	protected function checkValid()
+	{
+		if (empty($this->data['id'])) {
+			throw new HTTPException\InternalServerErrorException(static::class . ' record uninitialized');
+		}
+	}
 }
diff --git a/src/BaseRepository.php b/src/BaseRepository.php
index 30822091e..c0bcab18f 100644
--- a/src/BaseRepository.php
+++ b/src/BaseRepository.php
@@ -199,4 +199,12 @@ abstract class BaseRepository extends BaseFactory
 
 		return $models;
 	}
+
+	/**
+	 * @param BaseCollection $collection
+	 */
+	public function saveCollection(BaseCollection $collection)
+	{
+		$collection->map([$this, 'update']);
+	}
 }