Hi!
>>>>> "Peter" == Peter Andreasen <pandr@stripped> writes:
Peter> Hi,
Peter> The Manual says:
Peter> Each table index is queried and the best index that spans fewer than
Peter> 30% of the rows is used. If no such index can be found, a quick
Peter> table scan is used.
Note that the above only holds when you don't use LIMIT.
Peter> Well, sometimes I do stuff like
Peter> SELECT * FROM table WHERE id > 10000000 AND value='x' LIMIT 10;
Peter> and the index on column id can only limit the rows by, say, 50%.
Peter> Is it possible to force mysql to use the index in this case? The 'quick'
Peter> table scan is not _that_ quick when it has to go through >10M rows :-)
Using LIMIT, like above, should force MySQL to use the index instead
of doing a table scan.
Regards,
Monty
