Mysql group by: sorts the records with the largest time in each record.

Mysql tutorial group by, sorting the records with the largest time in each record

Select a. * from test,
(Select aid, max (day) max_day from test group by aid) B
Where a. aid = B. aid and a. day = B. max_day
Order by a. install desc

Test SQL

Create table if not exists 'test '(
'Id' int (10) unsigned not null auto_increment,
'Install' int (10) unsigned not null,
'Day' int (10) unsigned not null,
'Aid 'int (10) unsigned not null,
Primary key ('id ')
) Engine = myisam default charset = utf8 auto_increment = 12;

Insert into 'test' ('id', 'install', 'day', 'aid ') values
(1, 1232,200, 1 ),
(2, 2321,200 80809, 2 ),
(3, 1236,200 80810, 3 ),
(5, 4212,200 80809, 1 ),
(6, 2312,200 80810, 1 ),
(7, 1432,200, 1 ),
(8, 2421,200, 2 ),
(9, 4245,200 80811, 2 ),
(10,565 4, 20080810, 2 ),
(11,412,200, 3 );