protected function _fieldsQuote($alias, $field) {
		list($open, $close) = $this->_quotes;
		$aliasing = preg_split("/\s+as\s+/i", $field);

		if (isset($aliasing[1])) {
			list($aliasname, $fieldname) = $this->_splitFieldname($aliasing[0]);
			$alias = $aliasname ? : $alias;
			return "{$open}{$alias}{$close}.{$open}{$fieldname}{$close} as {$aliasing[1]}";
		} elseif ($alias) {
			return "{$open}{$alias}{$close}.{$open}{$field}{$close}";
		} else {
			return "{$open}{$field}{$close}";
		}
	}
protected function _fieldsQuote($alias, $field) {
		list($open, $close) = $this->_quotes;
		$aliasing = preg_split("/\s+as\s+/i", $field);

		if (isset($aliasing[1])) {
			list($aliasname, $fieldname) = $this->_splitFieldname($aliasing[0]);
			$alias = $aliasname ? : $alias;
			return "{$open}{$alias}{$close}.{$open}{$fieldname}{$close} as {$aliasing[1]}";
		} elseif ($alias) {
			return "{$open}{$alias}{$close}.{$open}{$field}{$close}";
		} else {
			return "{$open}{$field}{$close}";
		}
	}
protected function _fieldsQuote ( $ alias , $ field ) { list ( $ open , $ close ) = $ this -> _quotes ; $ aliasing = preg_split ( "/\s+as\s+/i" , $ field ) ; if ( isset ( $ aliasing [ 1 ] ) ) { list ( $ aliasname , $ fieldname ) = $ this -> _splitFieldname ( $ aliasing [ 0 ] ) ; $ alias = $ aliasname ? : $ alias ; return "{$open}{$alias}{$close}.{$open}{$fieldname}{$close} as {$aliasing[1]}" ; } elseif ( $ alias ) { return "{$open}{$alias}{$close}.{$open}{$field}{$close}" ; } else { return "{$open}{$field}{$close}" ; } }
Quotes fields, also handles aliased fields.

@see lithium\data\source\Database::fields()
@param string $alias
@param string $field
@return string The quoted field.
Quotes fields also handles aliased fields .