str_replace

Usage:
First param should be a field in a mysql query or a join condition
$this->_stick_field('table.fieldname = table2.fieldname2');

private function _stick_field($field)
{
    if (!preg_match('/`/', $field) && ($field != '*') && $this->_auto_sticks)
    {
        // Match any table names associated with a field name.
        if (preg_match('/^[a-zA-Z0-9\-_\*]+\.[a-zA-Z0-9\-_\*]+$/', $field))
        {
            $_arr_field = explode(".", $field);
            foreach ($_arr_field as $k => $v)
            {
                if ($v != '*')
                {
                    $_arr_field[$k] = '`'.$v.'`';
                }
            }
            return implode(".", $_arr_field);
        }

        /**
         * This is primarily used for join conditions.
         * The following tries to match as many table and field
         * names as posible, then splits them up, add backsticks
         * puts them togheter and replace the original string
         * with the formatted one.
         */
        preg_match_all('/([a-zA-Z0-9\-_]+\.[a-zA-Z0-9\-_]+)/', $field, $match);

        // Did we find any match?
        if (!empty($match[0]))
        {
            $_replace = array();
            // Search through the matches
            foreach ($match[0] as $k => $v) {
                $_arr_field = explode('.', $v);
                $_buffer = array();
                // Wrap field/table with backsticks
                foreach ($_arr_field as $value)
                {
                    if ($value != '*')
                    {
                        // Add the formatted field/value to the buffer
                        $_buffer[] = "`".$value."`";
                    }
                }
                // Store the formatted field/value in the replace var
                $_replace[$k] = implode('.', $_buffer);
            }
            // Replace the original string with the formatted string
            return str_replace($match[0], $_replace, $field);

        } else {
            return '`'.$field.'`';
        }
    }
    return $field;
} // _stick_field($field)