I have the following scenario:
2 Tables Patient and Activity
The Patient table contains: DNI, First and Last name. The Activity table contains: Patient's DNI, Activity.
Within the activity table I have repeated the DNI of the patients several times (since they perform several activities).
I need a query where I can bring my DNI without being repeated from the Activity table and the names and surnames of the Patient table.
I tried with count but it gives me errors using it together with group by