?
Solved

Grouping dates by week

Posted on 2012-03-26
3
Medium Priority
?
475 Views
Last Modified: 2012-03-27
I have a field called FieldA which has a date value.  I would like to group the dates by week. Week1 - Week52.  

What syntax can I use to assign a week number to each respective date.
We will use Sunday as the first day of the week and Saturday as the last day of the week.
0
Comment
Question by:morinia
3 Comments
 
LVL 16

Expert Comment

by:Wasim Akram Shaik
ID: 37768735
you can use this for getting the week number

select to_char(sysdate,'IW') from dual;

and use the same thing in group by also..
0
 
LVL 16

Expert Comment

by:DcpKing
ID: 37769411
Assuming SQL Server (for Oracle see previous answer):

select datepart(week, @dtDateValue) will return an integer corresponding to the ISO week number (week 1 is the week containing the first Thursday in the year; weeks start on Sunday).

Thus try grouping on datepart(week, FieldA):

select datepart(week, FieldA) as 'WeekNr', OtherField1, OtherField2, .....
from TableName
group by datepart(week, FieldA)

should give you the results with the week number at the front.

(Apologies for any typos - I don't have a copy of SQL Server in front of me to check things with)

Mike
0
 
LVL 11

Accepted Solution

by:
theartfuldazzler earned 2000 total points
ID: 37769958
Hi Morinia

I know you have asked SAS questions before, so here is the SAS solution:

DATA Input_DS;
  Date = '01Jan2012'd;
  OUTPUT;
  DATE = '31Dec2011'd;
  OUTPUT;
  DATE = '29JUL2009'd;
  OUTPUT;
  FORMAT Date Date9.;
RUN;

DATA Output_DS;
  Set Input_DS;
    Start_of_year = MDY(1,1, YEAR(Date));
	Week_no = INTCK("WEEK",Start_of_year,Date)+1;  
	/* One might need to make adjustments to the +1 depending on how one counts the first week */
	DROP Start_of_year;
RUN;

Open in new window

0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Backups and Disaster RecoveryIn this post, we’ll look at strategies for backups and disaster recovery.
In today's business world, data is more important than ever for informing marketing campaigns. Accessing and using data, however, may not come naturally to some creative marketing professionals. Here are four tips for adapting to wield data for insi…
Video by: Steve
Using examples as well as descriptions, step through each of the common simple join types, explaining differences in syntax, differences in expected outputs and showing how the queries run along with the actual outputs based upon a simple set of dem…
Despite its rising prevalence in the business world, "the cloud" is still misunderstood. Some companies still believe common misconceptions about lack of security in cloud solutions and many misuses of cloud storage options still occur every day. …

621 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question