SQL query - Join that returns the first two records of joining table

Question

I have two tables:

Patient

• pkPatientId
• FirstName
• Surname

PatientStatus

• pk

Answer 1

Check if your server supports windowed functions:

SELECT * 
FROM Patient p
LEFT JOIN PatientStatus ps ON p.pkPatientId = ps.fkPatientId
QUALIFY ROW_NUMBER() OVER (PARTITION BY ps.fkPatientId ORDER BY ps.StartDate) < 3

Another possibility, which should work with SQL Server 2005:

SELECT * FROM Patient p
LEFT JOIN ( 
    SELECT *, ROW_NUMBER(PARTITION BY fsPatientId ORDER by StartDate) rn
    FROM PatientStatus) ps
ON p.pkPatientId = ps.fkPatientID 
and ps.rn < 3