Ammar,
Zoom-search of date values needs improvement. Here is an example table:
CREATE TABLE IF NOT EXISTS `birthday` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` varchar(50) NOT NULL, `birthday` date NOT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=5 ;
INSERT INTO `birthday` (`id`, `name`, `birthday`) VALUES (1, 'A', '1950-01-01'), (2, 'B', '1950-02-02'), (3, 'C', '1960-03-03'), (4, 'D', '2000-04-04');
Generating a plot via zoom-search show that the same time elapsed between two days (in 1950) than in ten or forty years.
If you could convert these dates to a number of days (probably at the Javascript layer), the same way than in MySQL [0], you would get meaningful results. Of course you still need to display the unconverted date value.
[0] http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function...