mysql - 选择计算 DATETIME = DATE 的行数

Question

此查询将 DATETIME 转换为 DATE，并返回相同 DATE 的行数。

select*, DATE(call_end) AS Date,
COUNT(*) AS num_emails
from mk_calls mkc 
where call_end >= CURDATE() - INTERVAL 10 DAY
GROUP BY DATE(call_end)
ORDER BY call_start

我想知道如何在已知日期的情况下执行类似的查询？这可行吗？

$today_date = '2019-06-09';
//perform count query here

Answer 1

您可以使用 MySQLi 准备好的语句轻松完成此操作。

$sql = 'SELECT *, DATE(call_end) AS Date, COUNT(*) AS num_emails
    FROM mk_calls mkc 
    WHERE call_end >= ?
    GROUP BY DATE(call_end)
    ORDER BY call_start';

$today_date = '2019-06-09';
$stmt = $mysqli->prepare($sql);
$stmt->bind_param('s', $today_date);
$stmt->execute();

使用SELECT *通常是一个坏主意，特别是如果您使用GROUP BY