Best way to convert DateTime to “n Hours Ago” in SQL

Question

I wrote a SQL function to convert a datetime value in SQL to a friendlier \"n Hours Ago\" or \"n Days Ago\" etc type of message. And I was wondering if there was a better wa

Answer 1

As you say, I probably wouldn't do it in SQL, but as a thought exercise have a MySQL implementation:

CASE
    WHEN compare_date between date_sub(now(), INTERVAL 60 minute) and now() 
        THEN concat(minute(TIMEDIFF(now(), compare_date)), ' minutes ago')

    WHEN datediff(now(), compare_date) = 1 
        THEN 'Yesterday'

    WHEN compare_date between date_sub(now(), INTERVAL 24 hour) and now() 
        THEN concat(hour(TIMEDIFF(NOW(), compare_date)), ' hours ago')

    ELSE concat(datediff(now(), compare_date),' days ago')
END

Based on a similar sample seen on the MySQL Date and Time manual pages