original_string: public static function selectPrimaryKey(Connection $connection, $primary_key)
      {
          return static::selectOne($connection)
              ->where(static::$primary_key, $primary_key)
              ->execute();
      }
code: public static function selectPrimaryKey(Connection $connection, $primary_key)
      {
          return static::selectOne($connection)
              ->where(static::$primary_key, $primary_key)
              ->execute();
      }
code_tokens: public static function selectPrimaryKey ( Connection $ connection , $ primary_key ) { return static :: selectOne ( $ connection ) -> where ( static :: $ primary_key , $ primary_key ) -> execute ( ) ; }
docstring: Select a single entity matching a primary key.
  
  @param  Connection  $connection  A connection instance
  @param  mixed       $primary_key The primary key
  @return Entity|null The entity, or null if not found
docstring_tokens: Select a single entity matching a primary key .