A connection can control RAND() in following connection

show variables like 'thread_cache_size';

--connect foo,localhost,root

set rand_seed1=0, rand_seed2=0;

create table t1 (id int auto_increment key, b double);

--disable_query_log

--let $a=30

--while ($a) {

  insert t1 (b) values (rand());

  --dec $a

}

--enable_query_log

set rand_seed1=0, rand_seed2=0;

--disconnect foo

--connect bar,localhost,root

set @a=rand();

select * from t1 where b = @a;

drop table t1;

--disconnect bar

id      b

21      0.5129564902865854