diff --git a/Business/Finance/FinanceFormulas.php b/Business/Finance/FinanceFormulas.php
index dfca67533..c71c110ac 100644
--- a/Business/Finance/FinanceFormulas.php
+++ b/Business/Finance/FinanceFormulas.php
@@ -1197,14 +1197,14 @@ class FinanceFormulas
     /**
      * Rate of Inflation
      *
-     * @param float $oldCPI Consumer price index old
      * @param float $newCPI Consumer price index new
+     * @param float $oldCPI Consumer price index old
      *
      * @return float
      *
      * @since  1.0.0
      */
-    public static function getRateOfOnflation(float $oldCPI, float $newCPI) : float
+    public static function getRateOfOnflation(float $newCPI, float $oldCPI) : float
     {
         return $newCPI / $oldCPI - 1;
     }
@@ -1315,6 +1315,54 @@ class FinanceFormulas
         return $P * $r * $t;
     }
 
+    /**
+     * Simple Interest Rate
+     *
+     * @param float $I Interest
+     * @param float $P Principal
+     * @param int   $t Time
+     *
+     * @return float
+     *
+     * @since  1.0.0
+     */
+    public static function getSimpleInterestRate(float $I, float $P, int $t) : float
+    {
+        return $I / ($P * $t);
+    }
+
+    /**
+     * Simple Interest Principal
+     *
+     * @param float $I Interest
+     * @param float $r Rate
+     * @param int   $t Time
+     *
+     * @return float
+     *
+     * @since  1.0.0
+     */
+    public static function getSimpleInterestPrincipal(float $I, float $r, int $t) : float
+    {
+        return $I / ($r * $t);
+    }
+
+    /**
+     * Simple Interest Principal
+     *
+     * @param float $I Interest
+     * @param float $P Principal
+     * @param float $r Rate
+     *
+     * @return int
+     *
+     * @since  1.0.0
+     */
+    public static function getSimpleInterestTime(float $I, float $P, float $r) : int
+    {
+        return (int) round($I / ($P * $r));
+    }
+
     /**
      * Relative market share by share
      *
diff --git a/DataStorage/Database/Connection/ConnectionAbstract.php b/DataStorage/Database/Connection/ConnectionAbstract.php
index 7300e3a2b..20f4379a7 100644
--- a/DataStorage/Database/Connection/ConnectionAbstract.php
+++ b/DataStorage/Database/Connection/ConnectionAbstract.php
@@ -119,7 +119,7 @@ abstract class ConnectionAbstract implements ConnectionInterface
      */
     public function getDatabase() : string
     {
-        return $this->dbdata['database'];
+        return $this->dbdata['database'] ?? '';
     }
 
     /**
@@ -131,7 +131,7 @@ abstract class ConnectionAbstract implements ConnectionInterface
      */
     public function getHost() : string
     {
-        return $this->dbdata['host'];
+        return $this->dbdata['host'] ?? '';
     }
 
     /**
@@ -143,7 +143,7 @@ abstract class ConnectionAbstract implements ConnectionInterface
      */
     public function getPort() : int
     {
-        return (int) $this->dbdata['port'];
+        return (int) $this->dbdata['port'] ?? 0;
     }
 
     /**
diff --git a/DataStorage/Database/Connection/ConnectionFactory.php b/DataStorage/Database/Connection/ConnectionFactory.php
index ffe361716..9448235bd 100644
--- a/DataStorage/Database/Connection/ConnectionFactory.php
+++ b/DataStorage/Database/Connection/ConnectionFactory.php
@@ -33,6 +33,7 @@ class ConnectionFactory
      * Constructor.
      *
      * @since  1.0.0
+     * @codeCoverageIgnore
      */
     private function __construct()
     {
diff --git a/DataStorage/Database/Query/Builder.php b/DataStorage/Database/Query/Builder.php
index d60735bf5..996b6a15b 100644
--- a/DataStorage/Database/Query/Builder.php
+++ b/DataStorage/Database/Query/Builder.php
@@ -189,12 +189,6 @@ class Builder extends BuilderAbstract
      */
     public $raw = '';
 
-    protected $unionLimit = null;
-
-    protected $unionOffset = null;
-
-    protected $unionOrders = [];
-
     /**
      * Comparison OPERATORS.
      *
@@ -336,7 +330,7 @@ class Builder extends BuilderAbstract
      */
     public function newQuery() : Builder
     {
-        return new static($this->connection, $this->grammar);
+        return new static($this->connection, $this->isReadOnly);
     }
 
     /**
@@ -376,7 +370,7 @@ class Builder extends BuilderAbstract
         }
 
         $this->type = QueryType::RAW;
-        $this->raw  = $raw;
+        $this->raw  = rtrim($raw, ';');
 
         return $this;
     }
@@ -799,15 +793,6 @@ class Builder extends BuilderAbstract
         return $this->select('COUNT(' . $table . ')');
     }
 
-    /**
-     * Check if exists.
-     *
-     * @since  1.0.0
-     */
-    public function exists()
-    {
-    }
-
     /**
      * Select minimum.
      *
@@ -964,6 +949,10 @@ class Builder extends BuilderAbstract
      */
     public function update(...$tables) : Builder
     {
+        if($this->isReadOnly) {
+            throw new \Exception();
+        }
+
         $this->type = QueryType::UPDATE;
 
         foreach ($tables as $key => $table) {
@@ -979,6 +968,10 @@ class Builder extends BuilderAbstract
 
     public function delete() : Builder
     {
+        if($this->isReadOnly) {
+            throw new \Exception();
+        }
+
         $this->type = QueryType::DELETE;
 
         return $this;
diff --git a/DataStorage/Database/Query/Grammar/Grammar.php b/DataStorage/Database/Query/Grammar/Grammar.php
index ae77081aa..3ba97ff75 100644
--- a/DataStorage/Database/Query/Grammar/Grammar.php
+++ b/DataStorage/Database/Query/Grammar/Grammar.php
@@ -333,7 +333,7 @@ class Grammar extends GrammarAbstract
 
             return '(' . rtrim($values, ', ') . ')';
         } elseif ($value instanceof \DateTime) {
-            return $this->valueQuotes . $value->format('Y-m-d h:m:s') . $this->valueQuotes;
+            return $this->valueQuotes . $value->format('Y-m-d H:i:s') . $this->valueQuotes;
         } elseif (is_null($value)) {
             return 'NULL';
         } elseif (is_bool($value)) {
diff --git a/Log/FileLogger.php b/Log/FileLogger.php
index 4f2440a09..4bdbe4461 100644
--- a/Log/FileLogger.php
+++ b/Log/FileLogger.php
@@ -42,7 +42,7 @@ class FileLogger implements LoggerInterface
      * @var array
      * @since 1.0.0
      */
-    private $timings = [];
+    private static $timings = [];
 
     /**
      * Instance.
@@ -174,16 +174,22 @@ class FileLogger implements LoggerInterface
      *
      * @param string $id the ID by which this time measurement gets identified
      *
-     * @return void
+     * @return bool
      *
      * @since  1.0.0
      */
-    public function startTimeLog($id = '') /* : void */
+    public static function startTimeLog($id = '')  : bool
     {
+        if(isset(self::$timings[$id])) {
+            return false;
+        }
+
         $mtime = explode(' ', microtime());
         $mtime = $mtime[1] + $mtime[0];
 
-        $this->timings[$id] = ['start' => $mtime];
+        self::$timings[$id] = ['start' => $mtime];
+
+        return true;
     }
 
     /**
@@ -195,29 +201,15 @@ class FileLogger implements LoggerInterface
      *
      * @since  1.0.0
      */
-    public function endTimeLog($id = '') : int
+    public static function endTimeLog($id = '') : float
     {
         $mtime = explode(' ', microtime());
         $mtime = $mtime[1] + $mtime[0];
 
-        $this->timings[$id]['end']  = $mtime;
-        $this->timings[$id]['time'] = $mtime - $this->timings[$id]['start'];
+        self::$timings[$id]['end']  = $mtime;
+        self::$timings[$id]['time'] = $mtime - self::$timings[$id]['start'];
 
-        return $this->timings[$id]['time'];
-    }
-
-    /**
-     * Sorts timings descending.
-     *
-     * @param array [float] &$timings the timing array to sort
-     *
-     * @return void
-     *
-     * @since  1.0.0
-     */
-    public function timingSort(&$timings) /* : void */
-    {
-        uasort($timings, [$this, 'orderSort']);
+        return self::$timings[$id]['time'];
     }
 
     /**
@@ -261,25 +253,6 @@ class FileLogger implements LoggerInterface
         return strtr($message, $replace);
     }
 
-    /**
-     * Sorts all timings descending.
-     *
-     * @param array $a
-     * @param array $b
-     *
-     * @return int
-     *
-     * @since  1.0.0
-     */
-    private function orderSort($a, $b) : int
-    {
-        if ($a['time'] == $b['time']) {
-            return 0;
-        }
-
-        return ($a['time'] > $b['time']) ? -1 : 1;
-    }
-
     /**
      * Write to file.
      *
diff --git a/Math/Functions/Functions.php b/Math/Functions/Functions.php
index 6b735c79c..564f52aa0 100644
--- a/Math/Functions/Functions.php
+++ b/Math/Functions/Functions.php
@@ -227,7 +227,7 @@ class Functions
      */
     public static function isOdd($a) : bool
     {
-        return $a & 1;
+        return (bool) ($a & 1);
     }
 
     /**
@@ -241,7 +241,7 @@ class Functions
      */
     public static function isEven($a) : bool
     {
-        return !($a & 1);
+        return !((bool) ($a & 1));
     }
 
     /**
@@ -254,7 +254,7 @@ class Functions
      * @param mixed $length Circle size
      * @param mixed $start Start value
      *
-     * @return int
+     * @return int Lowest value is 0 and highest value is length - 1
      *
      * @since  1.0.0
      */
diff --git a/System/File/Local/LocalStorage.php b/System/File/Local/LocalStorage.php
index 4808e0194..ea248c7f5 100644
--- a/System/File/Local/LocalStorage.php
+++ b/System/File/Local/LocalStorage.php
@@ -16,6 +16,7 @@ declare(strict_types=1);
 namespace phpOMS\System\File\Local;
 use phpOMS\System\File\ContainerInterface;
 use phpOMS\System\File\StorageAbstract;
+use phpOMS\System\File\PathException;
 
 /**
  * Filesystem class.
@@ -184,7 +185,7 @@ class LocalStorage extends StorageAbstract
     public static function put(string $path, string $content, int $mode = 0) : bool
     {
         if(is_dir($path)) {
-            throw new \Exception();
+            throw new PathException($path);
         }
 
         return File::put($path, $content, $mode);
@@ -196,7 +197,7 @@ class LocalStorage extends StorageAbstract
     public static function get(string $path) : string
     {
         if(is_dir($path)) {
-            throw new \Exception();
+            throw new PathException($path);
         }
 
         return File::get($path);
@@ -208,7 +209,7 @@ class LocalStorage extends StorageAbstract
     public static function list(string $path, string $filter = '*') : array
     {
         if(is_file($path)) {
-            throw new \Exception();
+            throw new PathException($path);
         }
 
         return Directory::list($path, $filter);
@@ -228,7 +229,7 @@ class LocalStorage extends StorageAbstract
     public static function set(string $path, string $content) : bool
     {
         if(is_dir($path)) {
-            throw new \Exception();
+            throw new PathException($path);
         }
 
         return File::set($path, $content);
@@ -240,7 +241,7 @@ class LocalStorage extends StorageAbstract
     public static function append(string $path, string $content) : bool
     {
         if(is_dir($path)) {
-            throw new \Exception();
+            throw new PathException($path);
         }
 
         return File::append($path, $content);
@@ -252,7 +253,7 @@ class LocalStorage extends StorageAbstract
     public static function prepend(string $path, string $content) : bool
     {
         if(is_dir($path)) {
-            throw new \Exception();
+            throw new PathException($path);
         }
 
         return File::prepend($path, $content);
@@ -264,7 +265,7 @@ class LocalStorage extends StorageAbstract
     public static function extension(string $path) : string
     {
         if(is_dir($path)) {
-            throw new \Exception();
+            throw new PathException($path);
         }
 
         return File::extension($path);