select 1 random number from mysql database using asp.net c# -


how can select 1 random number database thats id autoincrement field.i have 25,000[id] records in database.each every time select 1 new random id. how can it.

use following sql(slow)

'select * tablename order rand() limit 1'

or can use(fast)

select * mytable, (select floor(max(mytable.id) * rand()) randid mytable) somerandid mytable.id = somerandid.randid

the inner select gives random id in right range. outer select looks right row in table.


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