SQL - RANDOM

11-24-08, 10:06 PM

Korgan

Hi,

i would ask what is the best method for random select from database. I
have table with 20k items..

- If i use ,,select * from table order by rand() limit 3", the query
took 0.0524 sec ... its slightly enough

- but if i generate rand id and then i use ,,select .... where id
in(rand1, rand2, rand3), the query took only 0.0005 sec, but
there is a problem that id doesnt exist

thanks for responses

11-24-08, 10:13 PM

Chris

Korgan wrote:
> Hi,
>
> i would ask what is the best method for random select from database. I
> have table with 20k items..
>
> - If i use ,,select * from table order by rand() limit 3", the query
> took 0.0524 sec ... its slightly enough

and as your table grows in size, it gets slower and slower.

Try this:

http://edrackham.com/featured/get-ra...order-by-rand/

There are other suggestions out there too, search for "mysql don't use
random()".

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