如何选择有多少用户具有不同的行值

我有名为“空缺”的 ROW - 它显示了某人去度假的次数。

一些具有值“0”。有些值“1”甚至“30”。没关系。

但是，我想选择每个“空缺”行不为 0 的用户。我该怎么做？

User1: Vacancy row 0

User2: Vacancy row 0

User3: Vacancy row 5

User4: Vacancy row 8

User5: Vacancy row 6000

User6: Vacancy row 100

User7: Vacancy row 0

_______

Total users who went to vacancy: 4. How can I echo number 4?

$sql = "SELECT Vacancy FROM users WHERE Vacancy > 0";

我当前的代码：

$sql25 = "SELECT Vacancy AS value_vacancy FROM users WHERE Vacancy > 0";

$result = $con->query($sql24);

if ($result->num_rows > 0) {

while($totalvacancy = $result->fetch_assoc()) {

$output25 = $totalvacancy ["value_vacancy"]; }

<html><?php echo number_format("$output25",0,",",".");?> people who went to vacancy

</html>

有错误

Warning: number_format() expects parameter 1 to be float, string given in on line

largeQ

浏览 149回答 2

2回答

沧海一幻觉

您的代码正在遍历查询结果并将的值分配给vacancy变量（可能未在循环外声明）。这不是您想要的（您实际上应该只计算查询返回的行数）。无论如何，我建议使用聚合查询来计算空缺用户的总数。这样的查询（没有子句的聚合group by）保证总是只返回一行，具有预期的计数。这避免了循环遍历结果的需要。让您的数据库为您完成聚合工作也比在 php.ini 中获取和循环更有效。您的代码可能如下所示：$sql25 = "SELECT COUNT(*) AS cnt_vacancy FROM users WHERE Vacancy > 0";if ($result = $con->query($sql24)) {    $row = $result->fetch_assoc();    <html><?php echo $row['cnt_vacancy']; ?> people went to vacancy</html>} else {    # error handling...}

FFIVE

您可以简单地使用!=as，SELECT * FROM user WHERE vacancy != 0;对于您的问题，请尝试一下。$query = "SELECT sum(vacancy) as total FROM user WHERE vacancy != 0";$result = $con->query($query);if(mysqli_num_rows($result) > 0){    $total = mysqli_fetch_assoc($result);    $total = floatval($totle['total']);}<html>    <?php echo number_format($total,0,",",".");?> people who went to vacancy    </html>

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