Athena 大于日期列中的条件

Question

我在 Athena 上尝试运行以下查询。

SELECT observation_date, COUNT(*) AS count
FROM db.table_name
WHERE observation_date > '2017-12-31'
GROUP BY observation_date

然而它产生了这个错误：

SYNTAX_ERROR: line 3:24: '>' cannot be applied to date, varchar(10)

我觉得这很奇怪。我的查询是否有错误或 Athena 无法处理日期列上的大于运算符？

谢谢！

Answer 1

在进行比较之前，您需要使用转换来正确设置日期格式。请尝试以下操作：

SELECT observation_date, COUNT(*) AS count
FROM db.table_name
WHERE observation_date > CAST('2017-12-31' AS DATE)
GROUP BY observation_date

在 Fiddler 中查看：SQL Fidle

更新 17/07/2019

为了反映评论

SELECT observation_date, COUNT(*) AS count
FROM db.table_name
WHERE observation_date > DATE('2017-12-31')
GROUP BY observation_date

Answer 2

您还可以使用 date 函数，它是 CAST(x AS date):

的方便别名

SELECT * 
FROM date_data
WHERE trading_date >= DATE('2018-07-06');

Answer 3

select * from my_schema.my_table_name where date_column = cast('2017-03-29' as DATE) limit 5

Athena greater than condition in date column