Yes, you are correct. I was thinking that wouldn't be the case, but it makes sense now.
I added indexes and then the query returned in a few seconds. Definitely have to have
indexes.
Thanks!
Dan Nelson wrote:
> In the last episode (Sep 18), Allen said:
>
>>I have two tables. One table is 13 million rows the other is about
>>250,000. I am trying to join the two to find users. The tables are not
>>indexed and I know that will effect the speed, but the join never
>>completes. I let it run for about 10 hours and the process was stuck in
>>the "sending" state, which I don't really understand. What is taking so
>>long? The join size should be no greater than 250,000 which is the size of
>>the second table. Yes???
>>I am using the default join_buffer size, which seems to low. Might this be
>>the problem?
>
>
> You _have_ to add indexes. Mysql is currently scanning the entire 250k
> table for each record in the big table to find matching records. You
> can verify this by running "EXPLAIN SELECT .. etc" on your query and
> multiplying all the "rows" values together.
>
--
Allen Brost
Motorola - DMTS
Allen.Brost@stripped
Work: (847)-435-2019
Cell: (847)-878-7784
