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datetimecastinggoogle-bigquerystring-to-datetime

How do I cast dd/mm/yyyy string into date in BigQuery?

I have 3 columns 1. dd/mm/yyyy (stored as a string) 2. app_id and #downloads of apps

I have to find unique ids of apps downloaded within a week.

Thank you

Solution

  • You can convert your dd/MM/yyyy strings into BigQuery timestamps using something like the following:

    SELECT TIMESTAMP(year + '-' + month + '-' + day) as output_timestamp
FROM (
  SELECT 
    REGEXP_EXTRACT(input_date, '.*/([0-9]{4})$') as year, 
    REGEXP_EXTRACT(input_date, '^([0-9]{2}).*') as day, 
    REGEXP_EXTRACT(input_date, '.*/([0-9]{2})/.*') AS month 
  FROM 
    (SELECT '30/10/2015' as input_date),
    (SELECT '25/01/2015' as input_date)
)

    Once you have converted them to timestamps, you may find the date and time functions useful, depending on what you're trying to do.