Question

我需要获得结果行计数

$this-> db = new mysqli("localhost", "***", "***", "***") or die("Error ".mysqli_error($link));
$this-> db -> set_charset("utf8");

$query = "SELECT steps.id, steps.description, steps.sort, services.`name` AS service_name, services.short_name AS service_short_name, terminals.`name` AS terminal_name, terminals.short_name AS terminal_short_name FROM steps INNER JOIN instructions ON steps.page_id = instructions.id INNER JOIN services ON instructions.service_id = services.id INNER JOIN terminals ON instructions.terminal_id = terminals.id WHERE services.short_name = '{$service}' AND terminals.`name` = '{$terminal}' ORDER BY steps.sort";

if ($stmt = $this->db-> prepare($query)) {
    $stmt -> execute();
    $stmt -> store_result();
    printf("row count: %d.\n", $stmt -> num_rows);
    $stmt -> close();
}

它返回零 - 0 但有一些像10-15行

Answer 1

虽然＆＃34;我做错了什么＆＃34;是这个网站的一个offtopic问题，答案是：

说到获得行数，你所做的一切都是正确的您遇到麻烦的唯一原因是您需要自行解决的一些数据/代码不一致问题。

说到使用预处理语句，你使用它们是错误的，直接在查询中添加变量，而你应该用占位符表示它们并稍后绑定。

php mysqli stmt count num_rows

1 个答案: