Presto - where子句中的静态日期和时间戳

Question

我很确定以下查询曾经在Presto上为我工作:

select segment, sum(count)
from modeling_trends
where segment='2557172' and date = '2016-06-23' and count_time between '2016-06-23 14:00:00.000' and '2016-06-23 14:59:59.000';
group by 1;

现在,当我运行它(在EMR上的Presto 0.147上)时,我收到错误,试图将varchar分配给日期/时间戳.

我可以使用它:

select segment, sum(count)
from modeling_trends
where segment='2557172' and date = cast('2016-06-23' as date) and count_time between cast('2016-06-23 14:00:00.000' as TIMESTAMP) and cast('2016-06-23 14:59:59.000' as TIMESTAMP)
group by segment;

但感觉很脏......有没有更好的方法呢？

Answer 1

与其他一些数据库不同,Presto不会自动在varchar和其他类型之间进行转换,即使对于常量也是如此.转换工作,但更简单的方法是使用类型构造函数:

WHERE segment = '2557172'
  AND date = date '2016-06-23'
  AND count_time BETWEEN timestamp '2016-06-23 14:00:00.000' AND timestamp '2016-06-23 14:59:59.000'

您可以在此处查看各种类型的示例:https://prestodb.io/docs/current/language/types.html