My mysql table carshes and I can't find the reason

My mysql table carshes and I can't find the reason

I have an online game site, and I get this error on my site:
Warning: mysql_query(): Unable to save result set in
/home/fravianx/public_html/tx25/GameEngine/Database/db_MYSQL.php on line
2750
and here is the part of code that makes the error :
function getTrainingList() { $q = "SELECT * FROM " . TB_PREFIX . "training
where vref != '' AND eachtime<=(1000*(".time()."-commence))"; $result =
mysql_query($q, $this->connection); return
$this->mysql_fetch_all($result); }
the code itself looks fine (well, at least to me) but somehow it makes the
"training" table in mysql database to crash (doesn't do what it supposed
to be doing, which is creating troops on players accounts)
I have tried everything I could find online but still couldn't fix this :(
can you help me with this?