Question

I have a table with two columns, date and score. I want to find something like:

• Sum as of 7 days ago
• Sum as of 6 days ago
• …
• Sum as of today

An individual thing could be found with

select sum(score) from my_table
where date <= DateAdd("d", -1, getdate) 

But I would like to not have to run a new query every time.

(I am using django, but pure SQL solutions are fine too.)

Answer 1

Use case statements to sum each value you care about.

SELECT 
(CASE WHEN date <= DateAdd("d", -1, getdate) THEN score ELSE 0 END) as sum1,
(CASE WHEN date <= DateAdd("d", -2, getdate) THEN score ELSE 0 END) as sum2, etc.