Question

我必须向最终用户显示系统状态：所以我有一组查询，以1min，5min，hour，day，month间隔显示发送的数据

$sentCount = new stdClass();
$sentCount->amon = $link->query("select * from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 2073600 ;")->num_rows;
$sentCount->amin = $link->query("select * from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 60 ;")->num_rows;
$sentCount->a5min = $link->query("select * from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 300 ;")->num_rows;
$sentCount->ahour = $link->query("select * from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 3600 ;")->num_rows;
$sentCount->aday = $link->query("select * from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 86400 ;")->num_rows;

但是这种风格的代码需要大量时间才能执行我如何更改它以获得更快的答案！？

Answer 1

似乎您只需要行计数。您当前代码的问题如下：

如果只想获取行数，则应使用内置的COUNT()函数。这样会更快。
第二，现在从数据库服务器到应用程序代码的数据包变得越来越小。您不是要获取所有行数据，而是现在只有一个数字。
另外，请阅读Why is SELECT * considered harmful?

尝试以下查询：

$sentCount = new stdClass();
$sentCount->amon = $link->query("select COUNT(*) as count from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 2073600 ;")->row['count'];
$sentCount->amin = $link->query("select COUNT(*) as count from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 60 ;")->row['count'];
$sentCount->a5min = $link->query("select COUNT(*) as count from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 300 ;")->row['count'];
$sentCount->ahour = $link->query("select COUNT(*) as count from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 3600 ;")->row['count'];
$sentCount->aday = $link->query("select COUNT(*) as count from row_sent where result='succes' and TIMESTAMPDIFF(SECOND, send_date , now()) < 86400 ;")->row['count'];

Answer 2

首先，您可以组合成一个查询，并使用IF和SUM来获得结果。

SELECT
    *,
    SUM(IF(TIMESTAMPDIFF(SECOND, send_date, NOW()) < 2073600,1,0)) AS MONTH,
    SUM(IF(TIMESTAMPDIFF(SECOND, send_date, NOW()) < 60,1,0)) AS one_min,
    SUM(IF(TIMESTAMPDIFF(SECOND, send_date, NOW()) < 300,1,0)) AS five_min,
    SUM(IF(TIMESTAMPDIFF(SECOND, send_date, NOW()) < 3600,1,0)) AS HOUR,
    SUM(IF(TIMESTAMPDIFF(SECOND, send_date, NOW()) < 86400,1,0)) AS DAY
    FROM
        row_sent
    WHERE
        result = 'succes';

合并查询以获得最快的答案

2 个答案: