Write a query that ?nds all students who took MAT123 from Professor Ann White but did not take MAT321 from her.

What will be an ideal response?

We will use DRC. The TRC solution is similar.
```
{SN|? Id,Addr,Status,Sem,Gr,PId,Dept (
Student(Id,SN,Addr,Status) AND
Transcript(Id,’MAT123’,Sem,Gr) AND
Teaching(PId,’MAT123’,Sem) AND
Professor(PId,’Ann White’,Dept) AND
NOT ? Sem1,Gr1 (
Transcript(Id,’MAT321’,Sem1,Gr1) AND
Teaching(PId,’MAT321’,Sem1) )
)}
```