PHP foreach 删除数组

Question

数组输出，我想删除其中1个值，剩余的值都显示出来。

数组：

Array
(
    [0] => Array
        (
            [uid] => 1
            [tid] => 0
            [username] => 123
            [truename] => 3333
            [groupid] => 1
        )

    [1] => Array
        (
            [uid] => 2
            [tid] => 0
            [username] => 321
            [truename] => 5
            [groupid] => 1
        )

    [2] => Array
        (
            [uid] => 4
            [tid] => 0
            [username] => 456
            [truename] => 5
            [groupid] => 2
        )

我只想显示 [groupid] => 2 的数组， [groupid] => 1 给删除。

foreach($db as $v){  

    if($v['groupid'] == 1){
        unset($db[$v['groupid']]);
    }
｝

如何写？ 求学习！！

Answer 1

foreach($db as $k=>$v){  

    if($v['groupid'] == 1){
        unset($db[$k]);
    }
｝

Answer 2

array_values(array_filter($db,function($i){return $i['groupid'] == 2;}))

Answer 3

unset() 函数