SQL-将月份字符串'08 -2019'转换为时间戳数据类型-01-08-2019

Question

I have a column - local_month - containing a string value "2019-08". Any ideas how I can convert this to a timestamp datatype?

My current approach was to get substrings of the value to yield a value of 01-08-2019. This still is giving me an error when I try to use it as a timestamp.

FORMAT_TIMESTAMP("%d-%m-%Y",TIMESTAMP(DATE(cast(SUBSTR(local_month,1,4) as int64),cast(SUBSTR(local_month,6,2) as int64),cast('01' as int64)))) as month  

Answer 1

You can use PARSE_DATE and then cast the output to timestamp as PARSE_DATE will return a DATE :

with parse_date AS (SELECT PARSE_DATE("%m-%Y", '08-2019') as date)

SELECT FORMAT_TIMESTAMP('%d-%m-%Y', CAST(date as TIMESTAMP)) from parse_date

Which will output the following:

Row |   f0_ 
------------------
1   |   01-08-2019

More information about PARSE_DATE function can be found in the public docs .

Answer 2

Just use one of the PARSE_() functions. In your case, PARSE_TIMESTAMP() :

SELECT PARSE_DATE('%m-%Y', '08-2019'),
       PARSE_DATETIME('%m-%Y', '08-2019'),
       PARSE_TIMESTAMP('%m-%Y', '08-2019')