Building an OOP SQL query builder

PHP 7 implements something called a context sensitive lexer. What this means is that words that are normally reserved can be used if the context allows. Thus, when building an object-oriented SQL builder, we can get away with using methods named and, or, not, and so on.

How to do it...

1. We define a Application\Database\Finder class. In the class, we define methods that match our favorite SQL operations:

   namespace Application\Database;
   class Finder
   {
     public static $sql      = '';
     public static $instance = NULL;
     public static $prefix   = '';
     public static $where    = array();
     public static $control  = ['', ''];
     
       // $a == name of table
       // $cols = column names
       public static function select($a, $cols = NULL)
       {
         self::$instance  = new Finder();
         if ($cols) {
              self::$prefix = 'SELECT ' . $cols . ' FROM ' . $a;
         } else {
           self::$prefix = 'SELECT * FROM ' . $a;
         }
         return self::$instance;
       }
     ...