In Relational Algebra, the Union operation requires:

SPIT system wants to make Registration number of students a kind of key in the

ENROLLED relation such that Registration number cannot have any duplicate entry or a null

value but other relations may be connected to ENROLLED relation through this attribute.

Which type of key is the attribute Registration number?

In Two-Phase Locking, during which phase can a transaction release locks but not acquire new ones?

Consider the following query:

π Name (σ Dept='CSE' (Student))

This represents which SQL query?

Consider the following relation and SQL query

Tables:

SQL Query:

SELECT e.Name

FROM EMPLOYEE e

WHERE Salary > (

    SELECT AVG(Salary)

    FROM EMPLOYEE

    WHERE DeptID = e.DeptID

);

What does this query return?

Consider

the following relation: Shipment (BoxNo, DeliveryAdd, Date, Payment) with the

following

functional dependencies:

FD1:

BoxNo ! DeliveryAdd

FD2:

fDate, DeliveryAddg ! Payment

According

to the rule of pseudo-transitivity, which of the following functional

dependencies

can be

derived?

a)

DeliveryAdd -> Payment

b)

fBoxNo, Dateg -> Payment

c)

fBoxNo, DeliveryAddg -> Payment

d)

fBoxNog -> Payment