How to convert UTC time to local timezones based on timezone column in bigquery?

问题

I've been trying to convert each UTC time back to the appropriate local timezone using standard SQL in GBQ, but couldn't find a good way to do it dynamically because I might have tons of different timezone name within the database. I'm wondering if anyone has an idea?

The table I have contains 2 different columns (see screenshot)

回答1:

Below example is for BigQuery Standard SQL

#standardSQL
WITH `project.dataset.yourtable` AS (
  SELECT 'Pacific/Honolulu' timezone, TIMESTAMP '2020-03-01 03:41:27 UTC' UTC_timestamp UNION ALL
  SELECT 'America/Los_Angeles',  '2020-03-01 03:41:27 UTC'
)
SELECT *, 
  DATETIME(UTC_timestamp, timezone) AS local_time
FROM `project.dataset.yourtable`

with output

Row timezone            UTC_timestamp           local_time   
1   Pacific/Honolulu    2020-03-01 03:41:27 UTC 2020-02-29T17:41:27  
2   America/Los_Angeles 2020-03-01 03:41:27 UTC 2020-02-29T19:41:27  

来源：https://stackoverflow.com/questions/60824817/how-to-convert-utc-time-to-local-timezones-based-on-timezone-column-in-bigquery