How to select sales of the first four weeks of release

[Bert_Change]

Hi all, 

I am relatively new to Looker. i'm able to work with explores, create Looks and dashboard based on basic (custom) filterring. I have little knowledge of LookML and SQL. 

I have a list of products and the dates they were sold. I want to know which products sold the most in the first four weeks. Probleem is: the dates that the products are released are all different. Anyone any tips on how I can tackle this problem? 

Many thanks in advance.

Regards,
Bert

[a_aleinikov · Accepted solution]

Hi @Bert_Change ,
To get sales in the first 4 weeks after release, you need a field like:

DATEDIFF(sale_date, release_date) <= 28

Then filter on that. If you don’t have release_date in your Explore, ask your dev to expose it or create a derived table.