Question $1(10$ points$)$

A check constraint is inter$-$relational.

Question $1$ options:

True

False

Question $2(10$ points$)$

A foreign key constraint is intra$-$relational.

Question $2$ options:

True

False

Question $3(10$ points$)$

A view exists physically.

Question $3$ options:

True

False

Question $4(10$ points$)$

A relation can have several candidate keys.

Question $4$ options:

True

False

Question $5(10$ points$)$

We consider the table Teaching below. Check all statements that are True. We consider an ideal DBMS that would enforce all reactive constraints.

CREATE TABLE Teaching $($

ProfId INTEGER,

CrsCode CHAR $(6),$

Semester CHAR $(6),$

PRIMARY KEY $($CrsCode$,$ Semester$),$

FOREIGN KEY $($CrsCode$)$ REFERENCES Course,

FOREIGN KEY $($ProfId$)$ REFERENCES Professor $($Id$))$

Select $3$ correct answer$($s$)$

Question $5$ options:

If we delete a professor in Professor, nothing happens in Teaching.

If we update a semester in Teaching, nothing happens in Professor.

If we delete a course $($CrsCode$)$ in Course, we delete the data about this course in Teaching.

If we delete a course $($CrsCode$)$ in Course, we set to null the value of CrsCode in Teaching.

Question $6(10$ points$)$

Check all that apply. We consider the constraint: In teaching assignment table that assigns professors to courses, each individual assignment should correspond to exactly one professor and one course. The constraint is $...$

Select $2$ correct answer$($s$)$

Question $6$ options:

Structural$/$syntactic

Semantic

Static

Dynamic

Question $7(10$ points$)$

MySQL SQL and PostgreSQL permit to define the same reactive and referential constraints.

Question $7$ options:

True

False

Question $8(10$ points$)$

Check all that apply. We consider the constraint: A class start time must be before its end time. The constraint is $...$

Select $2$ correct answer$($s$)$

Question $8$ options:

Structural$/$syntactic

Semantic

Static

Dynamic

Question $9(10$ points$)$

A foreign key in a relation R$1$ is a candidate key in a relation R$2.$

Question $9$ options:

True

False

Question $10(10$ points$)$

A relation has only one primary key, a candidate key designed as the primary one.

Question $10$ options:

True

False