MYSQL 分組

標準的分組Mysql，取的分組全部數據: select * from table where id = id group by id order by id desc limit 1,1;

當使用分組取數量時，先取的全部分組，而後取數量： sleect count() from (select count() from table where id = id group by id order by id desc limit 1,1) as g;

當對分組組內內容排序時，先對數據排序，而後分組取的排序後的數據： select * from (select * from table order by id desc) as g where id = id group by id limit 1,1;

當對分組組內內容排序和分組排序使用，各自排序： select * from (select * from table order by id desc) as g where id = id group by id order by id desc limit 1,1;