2 ms·
If you sort the result of a SELECT in such a way that can't use an index (i.e. a file-sort), you will get significant performance gains from MySQL by minimizing
by barrkel 7y ago
If you sort the result of a SELECT in such a way that can't use an index (i.e. a file-sort), you will get significant performance gains from MySQL by minimizing the columns accessed. MySQL materializes the rows then sorts them. Wider rows, more data shuffling.