final public function join($table, $cond, $type = 'LEFT')
    {

        if ($type != '') {
            $type = strtoupper(trim($type));

            if (!in_array($type, array('LEFT', 'RIGHT', 'OUTER', 'INNER', 'LEFT OUTER', 'RIGHT OUTER'))) {
                $type = '';
            } else {
                $type .= ' ';
            }
        }
        // Extract any aliases that might exist.  We use this information
        // in the _protect_identifiers to know whether to add a table prefix
        $this->traceTableAlias($table);

        // Strip apart the condition and protect the identifiers
        if (preg_match('/([\w\.]+)([\W\s]+)(.+)/', $cond, $match)) {
            $match[1] = $this->identifiers($match[1]);
            $match[3] = $this->identifiers($match[3]);

            $cond = $match[1] . $match[2] . $match[3];
        }
        // Assemble the JOIN statement
        $join = $type . 'JOIN ' . $this->identifiers($table) . ' ON ' . $cond;

        $this->arrayJoin[] = $join;
        if ($this->arrayCaching === TRUE) {
            $this->arrayCacheJoin[] = $join;
            $this->arrayCacheExists[] = 'join';
        }

        return $this;
    }