medoo::select_context PHP Method

    protected function select_context($table, $join, &$columns = null, $where = null, $column_fn = null)
    {
        $table = '"' . $table . '"';
        $join_key = is_array($join) ? array_keys($join) : null;
        if (isset($join_key[0]) && strpos($join_key[0], '[') === 0) {
            $table_join = array();
            $join_array = array('>' => 'LEFT', '<' => 'RIGHT', '<>' => 'FULL', '><' => 'INNER');
            foreach ($join as $sub_table => $relation) {
                preg_match('/(\\[(\\<|\\>|\\>\\<|\\<\\>)\\])?([a-zA-Z0-9_\\-]*)\\s?(\\(([a-zA-Z0-9_\\-]*)\\))?/', $sub_table, $match);
                if ($match[2] != '' && $match[3] != '') {
                    if (is_string($relation)) {
                        $relation = 'USING ("' . $relation . '")';
                    }
                    if (is_array($relation)) {
                        if (isset($relation[0])) {
                            $relation = 'USING ("' . implode($relation, '", "') . '")';
                        } else {
                            $joins = array();
                            foreach ($relation as $key => $value) {
                                $joins[] = (strpos($key, '.') > 0 ? '"' . str_replace('.', '"."', $key) . '"' : $table . '."' . $key . '"') . ' = ' . '"' . (isset($match[5]) ? $match[5] : $match[3]) . '"."' . $value . '"';
                            }
                            $relation = 'ON ' . implode($joins, ' AND ');
                        }
                    }
                    $table_join[] = $join_array[$match[2]] . ' JOIN "' . $match[3] . '" ' . (isset($match[5]) ? 'AS "' . $match[5] . '" ' : '') . $relation;
                }
            }
            $table .= ' ' . implode($table_join, ' ');
        } else {
            if (is_null($columns)) {
                if (is_null($where)) {
                    if (is_array($join) && isset($column_fn)) {
                        $where = $join;
                        $columns = null;
                    } else {
                        $where = null;
                        $columns = $join;
                    }
                } else {
                    $where = $join;
                    $columns = null;
                }
            } else {
                $where = $columns;
                $columns = $join;
            }
        }
        if (isset($column_fn)) {
            if ($column_fn == 1) {
                $column = '1';
                if (is_null($where)) {
                    $where = $columns;
                }
            } else {
                if (empty($columns)) {
                    $columns = '*';
                    $where = $join;
                }
                $column = $column_fn . '(' . $this->column_push($columns) . ')';
            }
        } else {
            $column = $this->column_push($columns);
        }
        return 'SELECT ' . $column . ' FROM ' . $table . $this->where_clause($where);
    }

 /**
  * @param $table
  * @param $join
  * @param null $columns
  * @param null $where
  * @param null $column_fn
  * @return string
  */
 protected function select_context($table, $join, &$columns = null, $where = null, $column_fn = null)
 {
     return parent::select_context($this->prefix . $table, $join, $columns, $where, $column_fn);
 }