Example :
CREATE TABLE history
(`User_ID` int, `startDate` date, `endDate` date, `Type` int)
;
INSERT INTO history
(`User_ID`, `startDate`, `endDate`, `Type`)
VALUES
(2, '2012-10-01', '2012-10-02', 0),
(2, '2012-10-03', '2012-10-04', 3),
(2, '2012-10-05', '2012-10-06', 3),
(2, '2012-10-05', '2012-10-06', 10),
(2, '2012-10-07', '2012-10-08', 1),
(2, '2012-10-07', '2012-10-08', 3),
(3, '2012-10-09', '2012-10-10', 6),
(3, '2012-10-09', '2012-10-10', <img src='http://www.yiiframework.com/forum/public/style_emoticons/default/cool.gif' class='bbc_emoticon' alt='8)' />,
(3, '2012-10-11', '2012-10-12', 0),
(3, '2012-10-11', '2012-10-12', 1)
;
My Db this is
I want a query for the following answer
(`User_ID`, `startDate`, `endDate`, `Type`,pre_val)
(2, '2012-10-01', '2012-10-02', 0,NULL),
(2, '2012-10-03', '2012-10-04', 3,NULL),
(2, '2012-10-05', '2012-10-06', 10,3),
(2, '2012-10-07', '2012-10-08', 3,1),
(3, '2012-10-09', '2012-10-10', 8,6),
(3, '2012-10-11', '2012-10-12', 1,0)
based on date and user id please share if anyone knows the query