Question

I would like to create a query that would count how many records were created in the last 7, 14 and 28 days. My result would return something like:

7Days  14Days  28Days  
21     35      56

I know how to for each timepsan e.g. 7 days, but I do I capture all three in one query?

select count(*) from Mytable
where Created > DATEADD(day,-8, getdate()) 

Answer 1

Also not pretty, but doesn’t rely on subqueries (table/column names are from AdventureWorks). The case statement returns 1 if it falls within your criteria, 0 otherwise – then you just sum the results :

select sum(case when datediff(day, modifieddate, getdate()) <= 7
                then 1 else 0 end) as '7days',
       sum(case when datediff(day, modifieddate, getdate()) > 7
                     and datediff(day, modifieddate, getdate()) <= 14
                then 1 else 0 end) as '14days',
       sum(case when datediff(day, modifieddate, getdate()) > 14
                     and datediff(day, modifieddate, getdate()) <= 28
                then 1 else 0 end) as '28days'
from sales.salesorderdetail

Edit: Updated the datediff function – the way it was written, it would return a negative number (assuming modifieddate was in the past) causing all items to fall under the first case. Thanks to Andriy M for pointing that out