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Sql question

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Last Modified: 2014-12-18
Hi Experts,

I have a table containing:

ID
PatientID
DateStarted
Subject

How do I get the ID of the latest day per patient, per subject?
I would prefer to have this in one query/view.
Comment
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Commented:
Try this:

SELECT tblYourTable.[PatientID], Last(tblYourTable.[DateStarted]) AS LastOfDateStarted, Last(tblYourTable.[Subject]) AS LastOfSubject
FROM tblYourTable
GROUP BY tblYourTable.[PatientID];

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Flyster
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Top Expert 2016

Commented:
try this query


SELECT A.*
 FROM TableX AS A
 INNER JOIN
 (SELECT PatientID, Max([DateStarted]) AS MaxOfDate, Subject
      FROM TableX  GROUP BY PatientID, Subject)  AS B
      ON A.[DateStarted]=B.MaxOfDate AND A.PatientID=B.PatientID AND A.Subject=B.Subject
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Author

Commented:
@Ray,
It works great,
Just one question, if I want to exclude a subject where do I put it?

@Flyster,
I cant see how your example would work in my case, I need the ID of the record containing the highest date of patient per subject.

Thanks,
Ben
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Commented:
Sorry, missed that part. How about this:
SELECT Last(tblYourTable.ID) AS LastOfID, tblYourTable.PatientID, Last(tblYourTable.DateStarted) AS LastOfDateStarted, Last(tblYourTable.Subject) AS LastOfSubject
FROM tblYourTable
GROUP BY tblYourTable.PatientID

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To exclude a particular subject, see the last line:
SELECT Last(tblYourTable.ID) AS LastOfID, tblYourTable.PatientID, Last(tblYourTable.DateStarted) AS LastOfDateStarted, Last(tblYourTable.Subject) AS LastOfSubject
FROM tblYourTable
GROUP BY tblYourTable.PatientID
HAVING (((Last(tblYourTable.Subject))<>"Enter_Your_Subject_Here"));

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Author

Commented:
@Flyster,

Last(tblYourTable.ID) AS LastOfID..Group by PatientID would give me the highest ID per patient, not necessary the ID that belongs to the records containing the highest date.

Re excluding one subject, can you tell me how to modify Ray's suggestion to include this portion?

Thanks,
Ben
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Top Expert 2016
Commented:
This one is on us!
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Author

Commented:
Excellent, Thank You!
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