如何计算列中包含特定数字的行数

Question

我想回显一个包含相同特定数字的行数的计数。

我的数据库中有一个名为“member_group_id”的列。

例如，领导组 ID 为“4”，某些成员在 db 中分配了此编号，因此我想执行如下操作：

$countLeaders = count($row['member_group_id'] == 4);

我该怎么做？

这是我的数据库查询：

$result = mysqli_query($con,"SELECT * FROM core_members WHERE member_group_id IN (4, 7, 8, 6, 11) ORDER BY 

    CASE member_group_id 

        WHEN '4' THEN 1  

        WHEN '7' THEN 2

        WHEN '8' THEN 3

        WHEN '6' THEN 4

        WHEN '11' THEN 5 

    END ASC, name ASC");

这是我的实际循环和期望的结果：

while($row = mysqli_fetch_array($result)){        

    $group = $row['member_group_id'];

    $countLeaders = count($group == 4);

}

echo "<span>" . $countLeaders . " Leaders</span>";

Answer 1

您只需要测试您感兴趣的值，然后将其添加到累加器中（如果它是正确的值）$row['member_group_id']$countLeaders = 0;while($row = mysqli_fetch_assoc($result)){&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; if ($row['member_group_id'] == '4') {&nbsp; &nbsp; &nbsp; &nbsp; $countLeaders++;&nbsp; &nbsp; }&nbsp; &nbsp; // other code if you have it}echo "<span>" . $countLeaders . " Leaders</span>";

Answer 2

如果我理解，你从你的查询中得到的所有结果都是一个数组，类似于：pg_fetch_all$result = [&nbsp; &nbsp; [&nbsp; &nbsp; &nbsp; &nbsp; 'id'&nbsp; &nbsp; &nbsp;=> 'whatever',&nbsp; &nbsp; &nbsp; &nbsp; 'and'&nbsp; &nbsp; => 'whatever',&nbsp; &nbsp; &nbsp; &nbsp; 'other'&nbsp; => 'whatever'&nbsp; &nbsp; &nbsp; &nbsp; 'fields' => 'whatever'&nbsp; &nbsp; &nbsp; &nbsp; 'member_group_id' => 1,&nbsp; &nbsp; ],&nbsp; &nbsp; [&nbsp; &nbsp; &nbsp; &nbsp; 'id'&nbsp; &nbsp; &nbsp;=> 'whatever',&nbsp; &nbsp; &nbsp; &nbsp; 'and'&nbsp; &nbsp; => 'whatever',&nbsp; &nbsp; &nbsp; &nbsp; 'other'&nbsp; => 'whatever'&nbsp; &nbsp; &nbsp; &nbsp; 'fields' => 'whatever'&nbsp; &nbsp; &nbsp; &nbsp; 'member_group_id' => 3,&nbsp; &nbsp; ],&nbsp; &nbsp; [&nbsp; &nbsp; &nbsp; &nbsp; 'id'&nbsp; &nbsp; &nbsp;=> 'whatever',&nbsp; &nbsp; &nbsp; &nbsp; 'and'&nbsp; &nbsp; => 'whatever',&nbsp; &nbsp; &nbsp; &nbsp; 'other'&nbsp; => 'whatever'&nbsp; &nbsp; &nbsp; &nbsp; 'fields' => 'whatever'&nbsp; &nbsp; &nbsp; &nbsp; 'member_group_id' => 1,&nbsp; &nbsp; ],]您想知道有多少条记录['member_group_id'] == 1您可以使用count(&nbsp; &nbsp; array_filter(&nbsp; &nbsp; &nbsp; &nbsp; function($item) { return ($item['member_group_id'] == 1); },&nbsp; &nbsp; &nbsp; &nbsp; $result&nbsp; &nbsp; ))array_filter遍历数组并仅保留函数返回 true 的项。

Answer 3

你不能在同一级别有多个时间相同键的数组，我解释说：$test['hello'] = 1;$test['hello'] = 5;因此，键将仅包含 。如果要计算具有相同值的所有键，可以编写如下代码：hello5$array = array('1', '1', '2', 'test' => '1', '1', '2', '3', '1', '9');$count = \count(array_keys($array, '1'));// output of $count is 5搜索与指定值对应的所有键，然后对所有键进行计数。