Driver_Database_Driver_MySQL::_compile_join_on

protected function _compile_join_on($join)
{
    if ($join['type'])
    {
        $sql = strtoupper($join['type']) . ' JOIN';
    }
    else
    {
        $sql = 'JOIN';
    }

    // Quote the table name that is being joined
    $sql .= ' ' . $this->quote_table($join['table'],true) . ' ON ';

    $conditions = array();
    foreach ($join['on'] as $condition)
    {
        // Split the condition
        list ($c1, $op, $c2) = $condition;

        if ($op)
        {
            // Make the operator uppercase and spaced
            $op = ' ' . strtoupper($op);
        }

        // Quote each of the identifiers used for the condition
        $conditions[] = $this->_quote_identifier($c1) . $op . ' ' . $this->_quote_identifier($c2);
    }

    // Concat the conditions "... AND ..."
    $sql .= '(' . implode(' AND ', $conditions) . ')';

    return $sql;
}