Mysql random rows
- by n00b
please read the whole question... 90% of you dont seem to do that and some of you only read the title obviously...
and if you dont know the solution, dont answer - i wont have to downvote you -.-''
im entertaining the idea of getting random rows directly from mysql.
what i found was
SELECT * FROM tablename WHERE somefield='something' ORDER BY RAND() LIMIT 5
but even i see how slow that would be..
is the only way to do this doing something like
SELECT * FROM tablename WHERE somefield='something' LIMIT RAND(aincrementvalue-5), 1
5 times?
or is there a way that i with my little knowlege of databases cant come up with ?
(no i dont want random indexes. i hate the idea of them...)
@commenters - please first look, then think, then look again, think again and then post. i
wont point fingers but i dislike stupid comments
and why i think random indexes are a nasty hack ?
it doesnt give you random results. it gives you x results from a random index in a predefined order
its like a gapless id only in the wrong order
if you fetch by 1 row and get true randomness you fall back to my method but with an additional junk field
finally the reason the field exists is only to serve as a helper to something that can be done without it with almost same performance (but the quality (randomness) is better), so it is a nasty hack ;)
i solved it, look @ my answer... if you think its incorrect please tell me :)
