MySQL Forums :: Performance :: Group By Perfomance MySQL vs MS SQL

It has to do a full table scan (as the EXPLAIN explains). I would expect that MsSql would have to do a table scan, too.

So, let's check the cache. How much RAM do you have?
* SHOW TABLE STATUS LIKE 'tbl'\G -- sizes
* SHOW VARIABLES LIKE '%buffer%'; -- cache size
and surround them with [ code ] and [ / code ]

And, does it run faster the second time you run it?