查找最活跃的玩家(表中符合条件的条目数最多)

时间:2015-11-20 01:11:52

标签: php mysql sql performance

我的目标是展示过去一个月内新记录数量最多的前五名玩家。

是否存在仅使用单个查询的方法,还是需要使用PHP来完成目标?这是我已经完成这个的简化版本(我想这更像是一个性能问题。另外请忽略CodeIgniter;它是多余的):

$res = [];

$q = $this->db1->query('SELECT authid, name FROM table WHERE date BETWEEN NOW() - INTERVAL 30 DAY AND NOW() ORDER BY date DESC');

foreach ($q->result_array() as $row) {
    if (isset($res[$row['authid']])) {
        $res[$row['authid']]['records'] += 1;
    } else {
        $res[$row['authid']] = [
            'records'   => 1,
            'name'      => $row['name']
        ];
    }
}

arsort($res);

return array_slice($res, 0, 5);

1 个答案:

答案 0 :(得分:4)

您需要group byorder by以及limit

SELECT authid, COUNT(*) as cnt
FROM table
WHERE date BETWEEN NOW() - INTERVAL 30 DAY AND NOW() 
GROUP BY authid 
ORDER BY cnt DESC
LIMIT 5;