diff --git a/README.md b/README.md
index 51144d7..250b22e 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ Add this line in your `composer.json` :
 ```json
 {
     "require": {
-        "m6web/redis-mock": "~1.2"
+        "m6web/redis-mock": "~2.0"
     }
 }
 ```
@@ -88,7 +88,10 @@ $factory     = new \M6Web\Component\RedisMock\RedisMockFactory();
 $myRedisMock = $factory->getAdapter('My\Redis\Library');
 ```
 
-**WARNING !** *RedisMock doesn't implement all Redis features and commands. The mock can have undesired behavior if your parent class uses unsupported features.*
+**WARNING !**
+
+  * *RedisMock doesn't implement all Redis features and commands. The mock can have undesired behavior if your parent class uses unsupported features.*
+  * *Storage is static and therefore shared by all instances.*
 
 *Note : the factory will throw an exception by default if your parent class implements unsupported commands. If you want even so partially use the mock, you can specify the second parameter when you build it `$factory->getAdapter('My\Redis\Library', true)`. The exception will then thrown only when the command is called.*
 
diff --git a/src/M6Web/Component/RedisMock/RedisMock.php b/src/M6Web/Component/RedisMock/RedisMock.php
index d1768eb..e097da0 100644
--- a/src/M6Web/Component/RedisMock/RedisMock.php
+++ b/src/M6Web/Component/RedisMock/RedisMock.php
@@ -10,53 +10,53 @@
 */
 class RedisMock
 {
-    protected $data          = array();
-    protected $dataTypes     = array();
-    protected $dataTtl       = array();
-    protected $pipeline      = false;
-    protected $savedPipeline = false;
-    protected $pipedInfo     = array();
+    protected static $data      = array();
+    protected static $dataTypes = array();
+    protected static $dataTtl   = array();
+    protected $pipeline         = false;
+    protected $savedPipeline    = false;
+    protected $pipedInfo        = array();
 
     public function reset()
     {
-        $this->data = array();
+        self::$data = array();
 
         return $this;
     }
 
     public function getData()
     {
-        return $this->data;
+        return self::$data;
     }
 
     public function getDataTtl()
     {
-        return $this->dataTtl;
+        return self::$dataTtl;
     }
 
     public function getDataTypes()
     {
-        return $this->dataTypes;
+        return self::$dataTypes;
     }
 
     // Strings
 
     public function get($key)
     {
-        if (!isset($this->data[$key]) || is_array($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || is_array(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(null);
         }
 
-        return $this->returnPipedInfo($this->data[$key]);
+        return $this->returnPipedInfo(self::$data[$key]);
     }
 
     public function set($key, $value, $seconds = null)
     {
-        $this->data[$key]      = $value;
-        $this->dataTypes[$key] = 'string';
+        self::$data[$key]      = $value;
+        self::$dataTypes[$key] = 'string';
 
         if (!is_null($seconds)) {
-            $this->dataTtl[$key] = time() + $seconds;
+            self::$dataTtl[$key] = time() + $seconds;
         }
 
         return $this->returnPipedInfo('OK');
@@ -78,24 +78,24 @@ public function setnx($key, $value)
 
     public function ttl($key)
     {
-        if (!array_key_exists($key, $this->data) || $this->deleteOnTtlExpired($key)) {
+        if (!array_key_exists($key, self::$data) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(-2);
         }
 
-        if (!array_key_exists($key, $this->dataTtl)) {
+        if (!array_key_exists($key, self::$dataTtl)) {
             return $this->returnPipedInfo(-1);
         }
 
-        return $this->returnPipedInfo($this->dataTtl[$key] - time());
+        return $this->returnPipedInfo(self::$dataTtl[$key] - time());
     }
 
     public function expire($key, $seconds)
     {
-        if (!array_key_exists($key, $this->data) || $this->deleteOnTtlExpired($key)) {
+        if (!array_key_exists($key, self::$data) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(0);
         }
 
-        $this->dataTtl[$key] = time() + $seconds;
+        self::$dataTtl[$key] = time() + $seconds;
 
         return $this->returnPipedInfo(1);
     }
@@ -109,17 +109,17 @@ public function incrby($key, $increment)
     {
         $this->deleteOnTtlExpired($key);
 
-        if (!isset($this->data[$key])) {
-            $this->data[$key] = (int) $increment;
-        } elseif (!is_integer($this->data[$key])) {
+        if (!isset(self::$data[$key])) {
+            self::$data[$key] = (int) $increment;
+        } elseif (!is_integer(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         } else {
-            $this->data[$key] += (int) $increment;
+            self::$data[$key] += (int) $increment;
         }
 
-        $this->dataTypes[$key] = 'string';
+        self::$dataTypes[$key] = 'string';
 
-        return $this->returnPipedInfo($this->data[$key]);
+        return $this->returnPipedInfo(self::$data[$key]);
     }
 
     public function decr($key)
@@ -131,17 +131,17 @@ public function decrby($key, $decrement)
     {
         $this->deleteOnTtlExpired($key);
 
-        if (!isset($this->data[$key])) {
-            $this->data[$key] = 0;
-        } elseif (!is_integer($this->data[$key])) {
+        if (!isset(self::$data[$key])) {
+            self::$data[$key] = 0;
+        } elseif (!is_integer(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
-        $this->data[$key] -= (int) $decrement;
+        self::$data[$key] -= (int) $decrement;
 
-        $this->dataTypes[$key] = 'string';
+        self::$dataTypes[$key] = 'string';
 
-        return $this->returnPipedInfo($this->data[$key]);
+        return $this->returnPipedInfo(self::$data[$key]);
     }
 
     // Keys
@@ -152,8 +152,8 @@ public function type($key)
             return $this->returnPipedInfo('none');
         }
 
-        if (array_key_exists($key, $this->dataTypes)) {
-            return $this->returnPipedInfo($this->dataTypes[$key]);
+        if (array_key_exists($key, self::$dataTypes)) {
+            return $this->returnPipedInfo(self::$dataTypes[$key]);
         } else {
             return $this->returnPipedInfo('none');
         }
@@ -165,7 +165,7 @@ public function exists($key)
             return $this->returnPipedInfo(false);
         }
 
-        return $this->returnPipedInfo(array_key_exists($key, $this->data));
+        return $this->returnPipedInfo(array_key_exists($key, self::$data));
     }
 
     public function del($key)
@@ -178,12 +178,12 @@ public function del($key)
 
         $deletedKeyCount = 0;
         foreach ( $keys as $k ) {
-            if ( isset($this->data[$k]) ) {
-                $deletedKeyCount += count($this->data[$k]);
-                unset($this->data[$k]);
-                unset($this->dataTypes[$k]);
-                if (array_key_exists($k, $this->dataTtl)) {
-                    unset($this->dataTtl[$k]);
+            if ( isset(self::$data[$k]) ) {
+                $deletedKeyCount += count(self::$data[$k]);
+                unset(self::$data[$k]);
+                unset(self::$dataTypes[$k]);
+                if (array_key_exists($k, self::$dataTtl)) {
+                    unset(self::$dataTtl[$k]);
                 }
             }
         }
@@ -196,7 +196,7 @@ public function keys($pattern)
         $pattern = preg_replace(array('#\*#', '#\?#', '#(\[[^\]]+\])#'), array('.*', '.', '$1+'), $pattern);
 
         $results = array();
-        foreach ($this->data as $key => $value) {
+        foreach (self::$data as $key => $value) {
             if (preg_match('#^' . $pattern . '$#', $key) and !$this->deleteOnTtlExpired($key)) {
                 $results[] = $key;
             }
@@ -215,20 +215,20 @@ public function sadd($key, $member)
 
         $this->deleteOnTtlExpired($key);
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
-        $isNew = !isset($this->data[$key]) || !in_array($member, $this->data[$key]);
+        $isNew = !isset(self::$data[$key]) || !in_array($member, self::$data[$key]);
 
         if ($isNew) {
-            $this->data[$key][] = $member;
+            self::$data[$key][] = $member;
         }
 
-        $this->dataTypes[$key] = 'set';
+        self::$dataTypes[$key] = 'set';
 
-        if (array_key_exists($key, $this->dataTtl)) {
-            unset($this->dataTtl[$key]);
+        if (array_key_exists($key, self::$dataTtl)) {
+            unset(self::$dataTtl[$key]);
         }
 
         return $this->returnPipedInfo((int) $isNew);
@@ -236,11 +236,11 @@ public function sadd($key, $member)
 
     public function smembers($key)
     {
-        if (!isset($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(array());
         }
 
-        return $this->returnPipedInfo($this->data[$key]);
+        return $this->returnPipedInfo(self::$data[$key]);
     }
 
     public function srem($key, $member)
@@ -249,14 +249,14 @@ public function srem($key, $member)
             throw new UnsupportedException('In RedisMock, `srem` command can not remove more than one member at once.');
         }
 
-        if (!isset($this->data[$key]) || !in_array($member, $this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || !in_array($member, self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(0);
         }
 
-        $this->data[$key] = array_diff($this->data[$key], array($member));
+        self::$data[$key] = array_diff(self::$data[$key], array($member));
 
-        if (0 === count($this->data[$key])) {
-            unset($this->dataTypes[$key]);
+        if (0 === count(self::$data[$key])) {
+            unset(self::$dataTypes[$key]);
         }
 
         return $this->returnPipedInfo(1);
@@ -264,7 +264,7 @@ public function srem($key, $member)
 
     public function sismember($key, $member)
     {
-        if (!isset($this->data[$key]) || !in_array($member, $this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || !in_array($member, self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(0);
         }
 
@@ -275,11 +275,11 @@ public function sismember($key, $member)
 
     public function lrem($key, $count, $value)
     {
-        if (!isset($this->data[$key]) || !in_array($value, $this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || !in_array($value, self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(0);
         }
 
-        $arr      = $this->data[$key];
+        $arr      = self::$data[$key];
         $reversed = false;
 
         if ($count < 0) {
@@ -299,80 +299,80 @@ public function lrem($key, $count, $value)
             return true;
         });
 
-        $deletedItems = count($this->data[$key]) - count($arr);
+        $deletedItems = count(self::$data[$key]) - count($arr);
 
         if ($reversed) {
             $arr = array_reverse($arr);
         }
 
-        $this->data[$key] = array_values($arr);
+        self::$data[$key] = array_values($arr);
 
         return $this->returnPipedInfo($deletedItems);
     }
 
     public function lpush($key, $value)
     {
-        if ($this->deleteOnTtlExpired($key) || !isset($this->data[$key])) {
-            $this->data[$key] = array();
+        if ($this->deleteOnTtlExpired($key) || !isset(self::$data[$key])) {
+            self::$data[$key] = array();
         }
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
-        array_unshift($this->data[$key], $value);
+        array_unshift(self::$data[$key], $value);
 
-        return $this->returnPipedInfo(count($this->data[$key]));
+        return $this->returnPipedInfo(count(self::$data[$key]));
     }
 
     public function rpush($key, $value)
     {
-        if ($this->deleteOnTtlExpired($key) || !isset($this->data[$key])) {
-            $this->data[$key] = array();
+        if ($this->deleteOnTtlExpired($key) || !isset(self::$data[$key])) {
+            self::$data[$key] = array();
         }
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
-        array_push($this->data[$key], $value);
+        array_push(self::$data[$key], $value);
 
-        return $this->returnPipedInfo(count($this->data[$key]));
+        return $this->returnPipedInfo(count(self::$data[$key]));
     }
 
     public function lpop($key)
     {
-        if (!isset($this->data[$key]) || !is_array($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || !is_array(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(null);
         }
 
-        return $this->returnPipedInfo(array_shift($this->data[$key]));
+        return $this->returnPipedInfo(array_shift(self::$data[$key]));
     }
 
     public function rpop($key)
     {
-        if (!isset($this->data[$key]) || !is_array($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || !is_array(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(null);
         }
 
-        return $this->returnPipedInfo(array_pop($this->data[$key]));
+        return $this->returnPipedInfo(array_pop(self::$data[$key]));
     }
 
     public function ltrim($key, $start, $stop)
     {
         $this->deleteOnTtlExpired($key);
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
-        } elseif (!isset($this->data[$key])) {
+        } elseif (!isset(self::$data[$key])) {
             return $this->returnPipedInfo('OK');
         }
 
         if ($start < 0) {
-            if (abs($start) > count($this->data[$key])) {
+            if (abs($start) > count(self::$data[$key])) {
                 $start = 0;
             } else {
-                $start = count($this->data[$key]) + $start;
+                $start = count(self::$data[$key]) + $start;
             }
         }
 
@@ -386,9 +386,9 @@ public function ltrim($key, $start, $stop)
             }
         }
 
-        $this->data[$key] = array_slice($this->data[$key], $start, $length);
+        self::$data[$key] = array_slice(self::$data[$key], $start, $length);
 
-        if (!count($this->data[$key])) {
+        if (!count(self::$data[$key])) {
             $this->stopPipeline();
             $this->del($key);
             $this->restorePipeline();
@@ -401,15 +401,15 @@ public function lrange($key, $start, $stop)
     {
         $this->deleteOnTtlExpired($key);
 
-        if (!isset($this->data[$key]) || !is_array($this->data[$key])) {
+        if (!isset(self::$data[$key]) || !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(array());
         }
 
         if ($start < 0) {
-            if (abs($start) > count($this->data[$key])) {
+            if (abs($start) > count(self::$data[$key])) {
                 $start = 0;
             } else {
-                $start = count($this->data[$key]) + $start;
+                $start = count(self::$data[$key]) + $start;
             }
         }
 
@@ -423,7 +423,7 @@ public function lrange($key, $start, $stop)
             }
         }
 
-        $data = array_slice($this->data[$key], $start, $length);
+        $data = array_slice(self::$data[$key], $start, $length);
 
         return $this->returnPipedInfo($data);
     }
@@ -434,16 +434,16 @@ public function hset($key, $field, $value)
     {
         $this->deleteOnTtlExpired($key);
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
-        $isNew = !isset($this->data[$key]) || !isset($this->data[$key][$field]);
+        $isNew = !isset(self::$data[$key]) || !isset(self::$data[$key][$field]);
 
-        $this->data[$key][$field] = $value;
-        $this->dataTypes[$key]    = 'hash';
-        if (array_key_exists($key, $this->dataTtl)) {
-            unset($this->dataTtl[$key]);
+        self::$data[$key][$field] = $value;
+        self::$dataTypes[$key]    = 'hash';
+        if (array_key_exists($key, self::$dataTtl)) {
+            unset(self::$dataTtl[$key]);
         }
 
         return $this->returnPipedInfo((int) $isNew);
@@ -453,7 +453,7 @@ public function hmset($key, $pairs)
     {
         $this->deleteOnTtlExpired($key);
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
@@ -469,20 +469,20 @@ public function hmset($key, $pairs)
 
     public function hget($key, $field)
     {
-        if (!isset($this->data[$key][$field]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key][$field]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(null);
         }
 
-        return $this->returnPipedInfo($this->data[$key][$field]);
+        return $this->returnPipedInfo(self::$data[$key][$field]);
     }
 
     public function hmget($key, $fields)
     {
         foreach ($fields as $field) {
-            if (!isset($this->data[$key][$field]) || $this->deleteOnTtlExpired($key)) {
+            if (!isset(self::$data[$key][$field]) || $this->deleteOnTtlExpired($key)) {
                 $result[$field] = null;
             } else {
-                $result[$field] = $this->data[$key][$field];
+                $result[$field] = self::$data[$key][$field];
             }
         }
 
@@ -495,18 +495,18 @@ public function hdel($key, $field)
             throw new UnsupportedException('In RedisMock, `hdel` command can not delete more than one entry at once.');
         }
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
-        if (!array_key_exists($key, $this->data) || $this->deleteOnTtlExpired($key)) {
+        if (!array_key_exists($key, self::$data) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(0);
         }
 
-        if (array_key_exists($field, $this->data[$key])) {
-            unset($this->data[$key][$field]);
-            if (0 === count($this->data[$key])) {
-                unset($this->dataTypes[$key]);
+        if (array_key_exists($field, self::$data[$key])) {
+            unset(self::$data[$key][$field]);
+            if (0 === count(self::$data[$key])) {
+                unset(self::$dataTypes[$key]);
             }
 
             return $this->returnPipedInfo(1);
@@ -517,25 +517,25 @@ public function hdel($key, $field)
 
     public function hgetall($key)
     {
-        if (!isset($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(array());
         }
 
-        return $this->returnPipedInfo($this->data[$key]);
+        return $this->returnPipedInfo(self::$data[$key]);
     }
 
     public function hexists($key, $field)
     {
         $this->deleteOnTtlExpired($key);
 
-        return $this->returnPipedInfo((int) isset($this->data[$key][$field]));
+        return $this->returnPipedInfo((int) isset(self::$data[$key][$field]));
     }
 
     // Sorted set
 
     public function zrange($key, $start, $stop, $withscores = false)
     {
-        if (!isset($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(array());
         }
 
@@ -566,7 +566,7 @@ public function zrange($key, $start, $stop, $withscores = false)
 
     public function zrevrange($key, $start, $stop, $withscores = false)
     {
-        if (!isset($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(array());
         }
 
@@ -597,20 +597,20 @@ public function zrevrange($key, $start, $stop, $withscores = false)
 
     protected function zrangebyscoreHelper($key, $min, $max, array $options = array(), $rev = false)
     {
-        if (!isset($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(array());
         }
 
-        if (!is_array($this->data[$key])) {
+        if (!is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
         if (!isset($options['limit']) || !is_array($options['limit']) || count($options['limit']) != 2) {
-            $options['limit'] = array(0, count($this->data[$key]));
+            $options['limit'] = array(0, count(self::$data[$key]));
         }
 
-        $set = $this->data[$key];
-        uksort($this->data[$key], function($a, $b) use ($set, $rev) {
+        $set = self::$data[$key];
+        uksort(self::$data[$key], function($a, $b) use ($set, $rev) {
             if ($set[$a] > $set[$b]) {
                 return $rev ? -1 : 1;
             } elseif ($set[$a] < $set[$b]) {
@@ -621,7 +621,7 @@ protected function zrangebyscoreHelper($key, $min, $max, array $options = array(
         });
 
         if ($min == '-inf' && $max == '+inf') {
-            $slice = array_slice($this->data[$key], $options['limit'][0], $options['limit'][1], true);
+            $slice = array_slice(self::$data[$key], $options['limit'][0], $options['limit'][1], true);
             if (isset($options['withscores']) && $options['withscores']) {
                 return $this->returnPipedInfo($slice);
             } else {
@@ -646,7 +646,7 @@ protected function zrangebyscoreHelper($key, $min, $max, array $options = array(
         };
 
         $results = array();
-        foreach ($this->data[$key] as $k => $v) {
+        foreach (self::$data[$key] as $k => $v) {
             if ($min == '-inf' && $isInfMax($v)) {
                 $results[$k] = $v;
             } elseif ($max == '+inf' && $isSupMin($v)) {
@@ -686,24 +686,24 @@ public function zadd($key, $score, $member) {
 
         $this->deleteOnTtlExpired($key);
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key])) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
             return $this->returnPipedInfo(null);
         }
 
-        $isNew = !isset($this->data[$key][$member]);
+        $isNew = !isset(self::$data[$key][$member]);
 
-        $this->data[$key][$member] = (int) $score;
-        $this->dataTypes[$key]     = 'zset';
-        if (array_key_exists($key, $this->dataTtl))
+        self::$data[$key][$member] = (int) $score;
+        self::$dataTypes[$key]     = 'zset';
+        if (array_key_exists($key, self::$dataTtl))
         {
-            unset($this->dataTtl[$key]);
+            unset(self::$dataTtl[$key]);
         }
 
         return $this->returnPipedInfo((int) $isNew);
     }
 
     public function zremrangebyscore($key, $min, $max) {
-        if (!isset($this->data[$key]) || $this->deleteOnTtlExpired($key)) {
+        if (!isset(self::$data[$key]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(0);
         }
 
@@ -729,14 +729,14 @@ public function zrem($key, $member) {
             throw new UnsupportedException('In RedisMock, `zrem` command can not remove more than one member at once.');
         }
 
-        if (isset($this->data[$key]) && !is_array($this->data[$key]) || !isset($this->data[$key][$member]) || $this->deleteOnTtlExpired($key)) {
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key]) || !isset(self::$data[$key][$member]) || $this->deleteOnTtlExpired($key)) {
             return $this->returnPipedInfo(0);
         }
 
-        unset($this->data[$key][$member]);
+        unset(self::$data[$key][$member]);
 
-        if (0 === count($this->data[$key])) {
-            unset($this->dataTypes[$key]);
+        if (0 === count(self::$data[$key])) {
+            unset(self::$dataTypes[$key]);
         }
 
         return $this->returnPipedInfo(1);
@@ -828,7 +828,7 @@ protected function returnPipedInfo($info)
 
     protected function deleteOnTtlExpired($key)
     {
-        if (array_key_exists($key, $this->dataTtl) and (time() > $this->dataTtl[$key])) {
+        if (array_key_exists($key, self::$dataTtl) and (time() > self::$dataTtl[$key])) {
             // clean datas
             $this->stopPipeline();
             $this->del($key);