What is the correct statement for describing the INTERSECT operation?

1. It returns the common values from the results of any two different queries
2. It returns the common rows of two different queries which have the same set of attributes in the select clause
3. It returns the common rows of two different queries which have the same condition in the where clause
4. None of these

What is the correct statement for describing the EXCEPT operation ?

1. It excludes all the rows present in both the queries
2. It includes the rows of the second query but excludes the results of the first query
3. It includes the rows of the first query but excludes the results of the second query
4. It includes all the rows of both queries but removes duplicates

Examine the structure of the EMPL and DEPT tables:

Table : EMPL

Table : DEPT

Evaluate this SQL statement :

SELECT employee_id, e.department_id, department_ name, salary 
FROM EMPL e, DEPT d
WHERE e.department_id = d.department_id;

Which SQL statement is equivalent to the above SQL statement ?

(a)

SELECT employee_id, department_id, department_name, salary 
FROM EMPL
WHERE department_id MATCHES department_id of DEPT;

(b)

SELECT employee_id, department_id, department_name,salary 
FROM EMPL
NATURAL JOIN DEPT;

(c)

SELECT employee_id, d.department_id, department_name,salary
FROM EMPL e 
JOIN DEPT d 
ON e.department_id = d.department_id;

(d)

SELECT employee_id, department_id, department_name,salary
FROM EMPL 
JOIN DEPT 
USING (e. department _id, d.department_id);