mysql查询没有任何意义

Question

嘿伙计们，我有一张mysql表，其中包含一些记录，如下图所示！

我有以下查询来计算指定时间范围内的记录数（sr13，r4和huawei的记录数）。

$date1 = "2012-01-02 03";
$date2 = "2014-12-30 24";
$counter_result = $this->db->query("select count(sr13) as count_sr13, count(r4) as count_r4, count(huawei) as count_huawei from cdrcount where date_time BETWEEN '$date1%' and '$date2%' ");

查询将三个字段的值返回为0。 查询有什么问题吗？

Answer 1

原因是date_time被隐式转换为字符串，因为BETWEEN中的值包含%。因此，它将字符串数据类型中的日期与包含%的值进行比较，显然没有匹配的记录，请尝试将其删除，

select  count(sr13) as count_sr13, 
        count(r4) as count_r4, 
        count(huawei) as count_huawei 
from    cdrcount 
where   date_time BETWEEN '$date1' and '$date2'

并且您的日期应格式化为有效日期，例如2012-01-02 03:00:00

Answer 2

尝试time_to_sec功能

select count(sr13) as count_sr13, count(r4) as
count_r4, count(huawei) as count_huawei from cdrcount 
where time_to_sec(date_time) 
BETWEEN time_to_sec('date1') and time_to_sec('date2');

Answer 3

要正确比较日期，您应该使用以下完整值：

$date1 = "2012-01-02 03:00:00";
$date2 = "2014-12-30 23:59:59";

从查询中删除%：

$counter_result = $this->db->query("select count(sr13) as count_sr13, count(r4) as count_r4, count(huawei) as count_huawei 
    from cdrcount 
    where date_time BETWEEN '$date1' and '$date2'");