Refactor class.Product.php and class.S.php for improved code readability and maintainability

libraries/grid/gdb.min.php

@@ -3,7 +3,7 @@
  * Medoo database framework
  * http://medoo.in
  * Version 0.9.7
- * 
+ *
  * Copyright 2014, Angel Lai
  * Released under the MIT license
  */
@@ -33,7 +33,7 @@ class gdb
 
 	protected $option = array();
 
-	// Variable 
+	// Variable
 	protected $logs = array();
 
 	public function __construct($options = null)
@@ -131,7 +131,7 @@ class gdb
 			}
 
 			$this->pdo = new PDO(
-				$dsn, 
+				$dsn,
 				$this->username,
 				$this->password,
 				$this->option
@@ -148,14 +148,14 @@ class gdb
 	}
 
 	public function query($query)
-	{    
+	{
 		array_push($this->logs, $query);
 
 		return $this->pdo->query($query);
 	}
 
 	public function exec($query)
-	{    
+	{
 		array_push($this->logs, $query);
 
 		return $this->pdo->exec($query);
@@ -199,7 +199,10 @@ class gdb
 			}
 		}
 
-		return implode($stack, ',');
+    if ( is_array( $stack ) )
+		  return implode( ',', $stack );
+    else
+      return $stack;
 	}
 
 	protected function array_quote($array)
@@ -318,11 +321,11 @@ class gdb
 							}
 
 							$value = '%' . $value . '%';
-              
+
 							$wheres[] = $column . ' LIKE ' . $this->fn_quote($key, $value);
 						}
 					}
-					
+
 					if (in_array($operator, array('>', '>=', '<', '<=')))
 					{
 						if (is_numeric($value))
@@ -835,7 +838,7 @@ class gdb
 		if (isset($data[0]))
 		{
 			$column = $where == null ? $join : $column;
-			
+
 			if (is_string($column) && $column != '*')
 			{
 				return $data[ 0 ][ $column ];