INTELLIGENT WORK FORUMS
FOR COMPUTER PROFESSIONALS

Log In

Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

Calculate visits based on cutoff date

Calculate visits based on cutoff date

(OP)
I have a group of patients participating in a special program. I need to compute the number of hospital visits for each patient before and after they joined this program.

Patient table looks like this:

CODE

PatientID      ActiveDate           InactiveDate          PreActiveVisits
111              7/1/2016           12/31/2016                   ?

Visits table looks like this:

PatientID           AdmitDate
111                 1/1/2016
111                 2/1/2016
111                 3/1/2016
111                 8/1/2016 

Need to populate the Patient table with a PreActiveVisits total of 3 but I'm not sure how to approach this without using a cursor.

RE: Calculate visits based on cutoff date

Would this query return the correct data?

CODE

Select  Visits.PatientId,
        Count(Visits.AdmitDate) As PreActiveVisits
From    Patient
        Inner Join Visits
          On Patient.PatientId = Visits.PatientId
          And Patient.ActiveDate <= Visits.AdmitDate
Group By Visits.PatientId 

-George
Microsoft SQL Server MVP
My Blogs
SQLCop
twitter
"The great things about standards is that there are so many to choose from." - Fortune Cookie Wisdom

RE: Calculate visits based on cutoff date

Try something like this:

CODE

WITH VisitCount (PatientID, VCount) AS
  (SELECT Visits.PatientID, COUNT(AdmitDate) 
     FROM Visits 
       JOIN Patient
         ON Visits.PatientID = Patient.PatientID
     WHERE Visits.AdmitDate < Patient.ActiveDate))

UPDATE Patient
  SET PreActiveVisits = VisitCount.VCount
  WHERE Patient.PatientID = VisitCount.PatientID 

Tamar

RE: Calculate visits based on cutoff date

(OP)
That did it - as always you make it look easy. For the update it would be easiest to use this as a cte? Thanks.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Tek-Tips Forums free from inappropriate posts.
The Tek-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members!

Resources

Close Box

Join Tek-Tips® Today!

Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free.

Here's Why Members Love Tek-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close