Question

In order to calculate projected sales for a given day, I need to query the last six weeks of data for a given day. For example, if I want projected sales for Friday, I need to query data from the last six Fridays only.

I’m assuming there is a way to do this within a query, just not sure exactly how. Any help or insight would be greatly appreciated, as always.

Thanks in advance.

Answer 1

The easiest way is to use a limit.

SELECT date, sales FROM yourtable WHERE DAYOFWEEK(date)=6 
ORDER BY date DESC LIMIT 6;

EDIT: To get this relative to today, just add CURDATE()

SELECT date, sales FROM yourtable WHERE DAYOFWEEK(date)=DAYOFWEEK(CURDATE()) 
ORDER BY date DESC LIMIT 6;