Hi all, trying to do something and have it be as efficient as possilble. My
question is if I have a table with say 10,000 rows in it, and I issue
a command like this
select * from table where number=1 order by rand() limit 1;
If 1000 rows would match this command does mysql first find all 1000 rows
and THEN randomly select 1 of those to return, OR does it just randomly
start somewhere and then stop when it finds one? The first method would
be really slow and inefficient, but I am afraid that is how it works? Is
there anyone out there that knows FOR SURE how the order by rand() operation
works? I can't find a specification out there for it.
Thanks,
Matt Heaton
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