方法一:
$num = 10;//幾條數據
$count = Db::name( 'topic' )->count();
$rand = mt_rand( 0, $count-1 );
$limit = $rand.','.$count;
$list = Db::name( 'topic' )->limit( $limit )->select();
shuffle( $list );
$new_ary = array_slice( $list, 0, $num );
方法二:
$new_ary = Db::name('topic')->orderRaw('rand()')->limit(10)->select();