tp5 随机查询一组数据方法,速度很快

随机查询一组数据方法

速度很快可大胆使用

function get random_data($table,$num){
    $countcus = db($table)->count();
    $min = db($table)->min('id');
    $max = $min+$countcus;
    if($countcus < $num){$num = $countcus;}
    $i = 1;
    $flag = 0;
    $ary = array();
    while($i<=$num){
        $rundnum = rand($min, $max);
        if($flag != $rundnum){
            if(!in_array($rundnum,$ary)){
                $ary[] = $rundnum;
                $flag = $rundnum;
            }else{
                $i--;
            }
            $i++;
        }
    }
    $data = db($table)->where('id','in',$ary,'or')->select();
    return $data;
}