3. Which statement about the <> operator is true? Mark for Review
(1) Points
The <> operator can be used when a single-row subquery returns only one row. (*)
The <> operator is NOT a valid SQL operator.
The <> operator CANNOT be used in a single-row subquery.
The <> operator returns the same result as the ANY operator in a subquery.
4. Which statement about subqueries is true? Mark for Review
(1) Points
Subqueries should be enclosed in double quotation marks.
Subqueries generally execute last, after the main or outer query executes.
Subqueries cannot contain group functions.
Subqueries are often used in a WHERE clause to return values for an unknown
conditional value. (*)
5. You need to create a report to display the names of products with a cost value
greater than the average cost of all products. Which SELECT statement should you
use? Mark for Review
(1) Points
SELECT product_name
FROM products
WHERE cost > AVG(cost);
SELECT product_name
FROM products
WHERE cost > (SELECT AVG(cost)
FROM products);
(*)
SELECT AVG(cost), product_name
FROM products
WHERE cost > AVG(cost)
GROUP by product_name;
SELECT product_name
FROM (SELECT AVG(cost) FROM product)
WHERE cost > AVG(cost);
6. The TEACHERS and CLASS_ASSIGNMENTS tables contain these columns:
TEACHERS
TEACHER_ID NUMBER(5) Primary Key
NAME VARCHAR2 (25)
SUBJECT_ID NUMBER(5)
CLASS_ID NUMBER(5)
CLASS_ASSIGNMENTS
CLASS_ID NUMBER (5) Primary Key
TEACHER_ID NUMBER (5)
DATE
MAX_CAPACITY NUMBER (3)
All MAX_CAPACITY values are greater than 10. Which two SQL statements correctly use
subqueries? (Choose two.)
Mark for Review
(1) Points
(Choose all correct answers)
SELECT *
FROM class_assignments
max_capacity = (SELECT AVG(max_capacity) FROM class_assignments GROUP BY
teacher_id);
SELECT *
FROM teachers
WHERE teacher_id = (SELECT teacher_id FROM class_assignments WHERE class_id =
45963);
(*)
SELECT *
FROM teachers
WHERE teacher_id LIKE (SELECT teacher_id FROM class_assignments WHERE
max_capacity > 1000);
SELECT *
FROM class_assignments
WHERE max_capacity = (SELECT AVG(max_capacity) FROM class_assignments);
(*)
SELECT *
FROM teachers
WHERE teacher_id = (SELECT teacher_id, class_assignments WHERE max_capacity > 0);
7. When creating a report of all employees earning more than the average salary for
their department, a __________ ____________ can be used to fifirst calculate the average salary
of each department, and then compare the salary for each employee to the average salary
of that employeeﾒs department. Mark for Review
(1) Points
WITH CLAUSE
GROUP BY
CORRELATED SUBQUERY (*)
8. Which statement is false? Mark for Review
(1) Points
The WITH clause retrieves the results of one or more query blocks.
The WITH clause stores the results for the user who runs the query.
The WITH clause decreases performance. (*)
The WITH clause makes the query simple to read.
9. Correlated Subqueries must reference the same tables in both the inner and outer
queries. (True or False?) Mark for Review
(1) Points
True
False (*)
10. When a multiple-row subquery uses the NOT IN operator (equivalent to <>ALL), if
one of the values returned by the inner query is a null value, the entire query returns:
Mark for Review
(1) Points
All rows that were selected by the inner query including the null values
No rows returned (*)
All rows that were selected by the inner query minus the null values
A list of Nulls
11. Examine the structures of the PARTS and MANUFACTURERS tables:
PARTS:
PARTS_ID VARCHAR2(25) PK
PARTS_NAME VARCHAR2(50)
MANUFACTURERS_ID NUMBER
COST NUMBER(5,2)
PRICE NUMBER(5,2)
MANUFACTURERS:
ID NUMBER PK
NAME VARCHAR2(30)
LOCATION VARCHAR2(20)
Assume that the tables have been populated with data including 100 rows in the PARTS
table, and 20 rows in the MANUFACTURERS table. Which SQL statement correctly uses a
subquery?
Mark for Review
(1) Points
SELECT parts_name, price, cost
FROM parts
WHERE manufacturers_id !=
(SELECT id
FROM manufacturers
WHERE LOWER(name) = 'cost plus');
SELECT parts_name, price, cost
FROM parts
WHERE manufacturers_id IN
(SELECT id
FROM manufacturers m
JOIN parts p
ON (m.id = p.manufacturers_id));
(*)
UPDATE parts SET price = price * 1.15
WHERE manufacturers_id =
(SELECT id
FROM manufacturers
WHERE UPPER(location) IN("ATLANTA", "BOSTON", "DALLAS"));
SELECT parts_name
FROM (SELECT AVG(cost) FROM manufacturers)
WHERE cost > AVG(cost);
12. You need to create a SELECT statement that contains a multiple-row subquery.
Which comparison operator(s) can you use? Mark for Review
(1) Points
=, <, and >
IN, ANY, and ALL (*)
LIKE
BETWEENﾅANDﾅ
13. You are looking for Executive information using a subquery.
What will the following SQL statement display?
SELECT department_id, last_name, job_id
FROM employees
WHERE department_id IN
(SELECT department_id FROM departments WHERE department_name = 'Executive');
Mark for Review
(1) Points
The department ID, department name, and last name for every employee in the
Executive department
The department ID, last name, and department name for every Executive in the
employees table
The department ID, last name, and job ID from departments for Executive
employees
The department ID, last name, and job ID for every employee in the Executive
department (*)
14. Evaluate the structure of the EMPLOYEES and DEPART_HIST tables:
EMPLOYEES
EMPLOYEE_ID NUMBER(9)
LAST_NAME VARCHAR2(25)
FIRST_NAME VARCHAR2(25)
DEPARTMENT_ID NUMBER(9)
MANAGER_ID NUMBER(9)
SALARY NUMBER(7,2)
DEPART_HIST:
EMPLOYEE_ID NUMBER(9)
OLD_DEPT_ID NUMBER(9)
NEW_DEPT_ID NUMBER(9)
CHANGE_DATE DATE
You want to generate a list of employees who are in department 10, but used to be in
department 15. Which query should you use?
Mark for Review
(1) Points
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id, department_id) =
(SELECT employee_id, new_dept_id
FROM depart_hist
WHERE new_dept_id = 15);
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id, department_id) IN
(SELECT employee_id, dept_id
FROM employees
WHERE old_dept_id = 15);
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id) IN
(SELECT employee_id
FROM employee_hist
WHERE old_dept_id = 15);
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id, department_id) IN
(SELECT employee_id, new_dept_id
FROM depart_hist
WHERE old_dept_id = 15) AND new_dept_id = 10;
(*)
15. Which of the following best describes the meaning of the ANY operator? Mark
for Review
(1) Points
Equal to any member in the list
Equal to each value in the list
Compare value to the fifirst value returned by the subquery
Compare value to each value returned by the subquery (*)
1. Table aliases must be used when you are writing correlated subqueries. (True or
false?) Mark for Review
(1) Points
True
False (*)
2. Oracle allows you to write named subqueries in one single statement, as long as you
start your statement with the keyword WITH. True or False? Mark for Review
(1) Points
True (*)
False
3. Which statement is false? Mark for Review
(1) Points
The WITH clause decreases performance. (*)
The WITH clause makes the query simple to read.
The WITH clause stores the results for the user who runs the query.
The WITH clause retrieves the results of one or more query blocks.
4. Subqueries can only be placed in the WHERE clause. True or False? Mark for
Review
(1) Points
True
False (*)
5. Which operator can be used with a multiple-row subquery? Mark for Review
(1) Points
IN (*)
LIKE
<>
=
6. Using a subquery in which clause will return a syntax error? Mark for Review
(1) Points
WHERE
FROM
HAVING
You can use subqueries in all of the above clauses. (*)
7. Which comparison operator can only be used with a single-row subquery? Mark
for Review
(1) Points
IN
<> (*)
ANY
ALL
8. Subqueries are limited to four per SQL transaction. True or False? Mark for
Review
(1) Points
True
False (*)
9. You need to produce a report that contains all employee-related information for
those employees who have Brad Carter as a supervisor. However, you are not sure which
supervisor ID belongs to Brad Carter. Which query should you issue to accomplish this
task? Mark for Review
(1) Points
SELECT *
FROM employees
WHERE supervisor_id = (SELECT supervisor_id
FROM employees
WHERE last_name = 'Carter');
SELECT *
FROM supervisors
WHERE supervisor_id =
(SELECT supervisor_id
FROM employees
WHERE last_name = 'Carter');
SELECT *
FROM employees
WHERE supervisor_id =
(SELECT employee_id
FROM employees
WHERE last_name = 'Carter');
(*)
SELECT *
FROM supervisors
WHERE supervisor_id =
(SELECT employee_id
FROM supervisors
WHERE last_name = 'Carter');
10. Which operator or keyword cannot be used with a multiple-row subquery? Mark
for Review
(1) Points
>
= (*)
ANY
ALL
11. When a multiple-row subquery uses the NOT IN operator (equivalent to <>ALL), if
one of the values returned by the inner query is a null value, the entire query returns:
Mark for Review
(1) Points
A list of Nulls
No rows returned (*)
All rows that were selected by the inner query including the null values
All rows that were selected by the inner query minus the null values
12. Evaluate this SQL statement:
SELECT employee_id, last_name, salary
FROM employees
WHERE department_id IN
(SELECT department_id
FROM employees
WHERE salary > 30000 AND salary < 50000);
Which values will be displayed?
Mark for Review
(1) Points
Only employees who earn more than $30,000.
All employees who work in a department with employees who earn more than
$30,000 and more than $50,000.
All employees who work in a department with employees who earn more than
$30,000, but less than $50,000. (*)
Only employees who earn less than $50,000.
13. Group functions can be used in multiple-row subqueries in the HAVING and GROUP
BY clauses. True or False? Mark for Review
(1) Points
True (*)
False
14. The SQL multiple-row subquery extends the capability of the single-row syntax
through the use of which three comparison operators? Mark for Review
(1) Points
IN, ANY, and ALL (*)
IN, ANY, and EVERY
IN, ALL, and EVERY
IN, ANY, and EQUAL
15. Evaluate the structure of the EMPLOYEES and DEPART_HIST tables:
EMPLOYEES
EMPLOYEE_ID NUMBER(9)
LAST_NAME VARCHAR2(25)
FIRST_NAME VARCHAR2(25)
DEPARTMENT_ID NUMBER(9)
MANAGER_ID NUMBER(9)
SALARY NUMBER(7,2)
DEPART_HIST:
EMPLOYEE_ID NUMBER(9)
OLD_DEPT_ID NUMBER(9)
NEW_DEPT_ID NUMBER(9)
CHANGE_DATE DATE
You want to generate a list of employees who are in department 10, but used to be in
department 15. Which query should you use?
Mark for Review
(1) Points
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id, department_id) =
(SELECT employee_id, new_dept_id
FROM depart_hist
WHERE new_dept_id = 15);
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id, department_id) IN
(SELECT employee_id, dept_id
FROM employees
WHERE old_dept_id = 15);
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id, department_id) IN
(SELECT employee_id, new_dept_id
FROM depart_hist
WHERE old_dept_id = 15) AND new_dept_id = 10;
(*)
SELECT employee_id, last_name, fifirst_name, department_id
FROM employees
WHERE (employee_id) IN
(SELECT employee_id
FROM employee_hist
WHERE old_dept_id = 15);
1. The Oracle server performs a correlated subquery when the subquery references a
column from a table referred to in the parent. True or False? Mark for Review
(1) Points
True (*)
False
2. The WITH clause is a way of creating extra tables in the database. (True or False?)
Mark for Review
(1) Points
True
False (*)
3. In a correlated subquery, the outer and inner queries are joined on one or more
columns. (True or False?) Mark for Review
(1) Points
True (*)
False
4. If a single-row subquery returns a null value and uses the equality comparison
operator, what will the outer query return? Mark for Review
(1) Points
All the rows in the table
No rows (*)
A null value
An error
5. Examine the structure of the EMPLOYEE, DEPARTMENT, and ORDERS tables.
EMPLOYEE:
EMPLOYEE_ID NUMBER(9)
LAST_NAME VARCHAR2(25)
FIRST_NAME VARCHAR2(25)
DEPARTMENT_ID NUMBER(9)
DEPARTMENT:
DEPARTMENT_ID NUMBER(9)
DEPARTMENT_NAME VARCHAR2(25)
CREATION_DATE DATE
ORDERS:
ORDER_ID NUMBER(9)
EMPLOYEE_ID NUMBER(9)
DATE DATE
CUSTOMER_ID NUMBER(9)
You want to display all employees who had an order after the Sales department was
established. Which of the following constructs would you use?
Mark for Review
(1) Points
A MERGE statement
A group function
The HAVING clause
A single-row subquery (*)
6. Single row subqueries may not include this operator: Mark for Review
(1) Points
=
>
<>
ALL (*)
7. The SQL multiple-row subquery extends the capability of the single-row syntax
through the use of which three comparison operators? Mark for Review
(1) Points
IN, ANY, and EQUAL
IN, ANY, and ALL (*)
IN, ALL, and EVERY
IN, ANY, and EVERY
8. Which of the following best describes the meaning of the ANY operator? Mark
for Review
(1) Points
Equal to each value in the list
Equal to any member in the list
Compare value to the fifirst value returned by the subquery
Compare value to each value returned by the subquery (*)
9. Which comparison operator would you use to compare a value to every value
returned by a subquery? Mark for Review
(1) Points
IN
ANY
SOME
ALL (*)
10. A multiple-row operator expects how many values? Mark for Review
(1) Points
One or more (*)
Only one
Two or more
None
11. Evaluate this SELECT statement:
SELECT player_id, name
FROM players
WHERE team_id IN
(SELECT team_id
FROM teams
WHERE team_id > 300 AND salary_cap > 400000);
What would happen if the inner query returned a NULL value?
Mark for Review
(1) Points
A syntax error in the outer query would be returned.
No rows would be returned by the outer query. (*)
A syntax error in the inner query would be returned.
All the rows in the PLAYER table would be returned by the outer query.
12. You need to create a SELECT statement that contains a multiple-row subquery.
Which comparison operator(s) can you use? Mark for Review
(1) Points
LIKE
BETWEENﾅANDﾅ
IN, ANY, and ALL (*)
=, <, and >
13. You need to display all the players whose salaries are greater than or equal to John
Brown's salary. Which comparison operator should you use? Mark for Review
(1) Points
=
<=
>= (*)
>
14. What will the following statement return:
SELECT last_name, salary
FROM employees
WHERE salary < (SELECT salary
FROM employees
WHERE employee_id = 103);
Mark for Review
(1) Points
A list of last_names and salaries of employees who make more than employee 103
A list of last_names and salaries of employees who make less than employee 103 (*)
A list of fifirst_names and salaries of employees making less than employee 103
Nothing. It is an invalid statement.
15. Which of the following is TRUE regarding the order of subquery execution? Mark
for Review
(1) Points
The subquery executes once after the main query.
The result of the main query is used with the subquery.
The subquery executes once before the main query. (*)
The outer query is executed fifirst.
1. Examine the structure of the EMPLOYEE, DEPARTMENT, and ORDERS tables.
EMPLOYEE:
EMPLOYEE_ID NUMBER(9)
LAST_NAME VARCHAR2(25)
FIRST_NAME VARCHAR2(25)
DEPARTMENT_ID NUMBER(9)
DEPARTMENT:
DEPARTMENT_ID NUMBER(9)
DEPARTMENT_NAME VARCHAR2(25)
CREATION_DATE DATE
ORDERS:
ORDER_ID NUMBER(9)
EMPLOYEE_ID NUMBER(9)
DATE DATE
CUSTOMER_ID NUMBER(9)
You want to display all employees who had an order after the Sales department was
established. Which of the following constructs would you use?
Mark for Review
(1) Points
A group function
The HAVING clause
A single-row subquery (*)
A MERGE statement
2. If a single-row subquery returns a null value and uses the equality comparison
operator, what will the outer query return? Mark for Review
(1) Points
No rows (*)
A null value
All the rows in the table
An error
3. The result of this statement will be:
SELECT last_name, job_id, salary, department_id
FROM employees
WHERE job_id =
(SELECT job_id
FROM employees
WHERE employee_id = 141) AND
department_id =
(SELECT department_id
FROM departments
WHERE location_id =1500);
Mark for Review
(1) Points
Only the employees whose job id matches employee 141 and who work in location
1500 (*)
All employees from Location 1500 will be displayed
All employees with the department id of 141
An error since you canﾒt get data from two tables in the same subquery
4. Which answer is INCORRECT? The parent statement of a correlated subquery can
be: Mark for Review
(1) Points
A SELECT statement
An UPDATE statement
A DELETE statement
An INSERT statement (*)
5. Table aliases must be used when you are writing correlated subqueries. (True or
false?) Mark for Review
(1) Points
True
False (*)
6. The WITH clause enables a SELECT statement to defifine the subquery block at the
start of the query, process the block just once, label the results, and then refer to the
results multiple times. True or False? Mark for Review
(1) Points
True (*)
False
7. Which of the following statements is a true guideline for using subqueries? Mark
for Review
(1) Points
The outer and inner queries can reference more than one table. They can get data
from different tables. (*)
Do not enclose the subquery in parentheses
Only one WHERE clause can be used for a SELECT statement, and if specifified, it
must be the outer query.
Place the subquery on the left side of the comparison condition.
8. You need to create a report to display the names of products with a cost value
greater than the average cost of all products. Which SELECT statement should you
use? Mark for Review
(1) Points
SELECT product_name
FROM (SELECT AVG(cost) FROM product)
WHERE cost > AVG(cost);
SELECT AVG(cost), product_name
FROM products
WHERE cost > AVG(cost)
GROUP by product_name;
SELECT product_name
FROM products
WHERE cost > (SELECT AVG(cost)
FROM products);
(*)
SELECT product_name
FROM products
WHERE cost > AVG(cost);
9. You need to display all the players whose salaries are greater than or equal to John
Brown's salary. Which comparison operator should you use? Mark for Review
(1) Points
>= (*)
=
<=
>
10. Evaluate this SELECT statement:
SELECT customer_id, name
FROM customer
WHERE customer_id IN
(SELECT customer_id
FROM customer
WHERE state_id = 'GA' AND credit_limit > 500.00);
What would happen if the inner query returned null?
Mark for Review
(1) Points
Only the rows with CUSTOMER_ID values equal to null would be selected.
No rows would be returned by the outer query. (*)
An error would be returned.
All the rows in the table would be selected.
11. Which statement about the ANY operator, when used with a multiple-row subquery,
is true? Mark for Review
(1) Points
The ANY operator is a synonym for the ALL operator.
The ANY operator can be used with the LIKE and IN operators.
The ANY operator compares every value returned by the subquery. (*)
The ANY operator can be used with the DISTINCT keyword.
12. Multiple-row subqueries must have NOT, IN, or ANY in the WHERE clause of the
inner query. True or False? Mark for Review
(1) Points
True
False (*)
13. Group functions can be used in multiple-row subqueries in the HAVING and GROUP
BY clauses. True or False? Mark for Review
(1) Points
True (*)
False
14. The salary column of the f_staffs table contains the following values:
4000
5050
6000
11000
23000
Which of the following statements will return the last_name and fifirst_name of those
employees who earn more than 5000?
Mark for Review
(1) Points
SELECT last_name, fifirst_name
FROM f_staffs
WHERE salary = (SELECT salary FROM f_staffs WHERE salary < 5000);
SELECT last_name, fifirst_name
FROM f_staffs
WHERE salary = (SELECT salary FROM f_staffs WHERE salary > 5000);
SELECT last_name, fifirst_name
FROM f_staffs
WHERE salary IN (SELECT salary FROM f_staffs WHERE salary > 5000);
(*)
SELECT last_name, fifirst_name
FROM f_staffs
WHERE salary IN
(SELECT last_name, fifirst_name FROM f_staffs WHERE salary <5000 o:p="">
Correct Correct
15. You need to create a SELECT statement that contains a multiple-row
subquery. Which comparison operator(s) can you use? Mark for Review
(1) Points
LIKE
IN, ANY, and ALL (*)
=, <, and >
BETWEENﾅANDﾅ
Which of the following is a valid reason why the query below will not execute successfully?
SELECT employee_id, last_name, salary
FROM employees
WHERE department_id =
(SELECT department_id FROM employees WHERE last_name like '%u%');
Mark for Review
(1) Points
First subquery not enclosed in parentheses.
The greater than operator is not valid.*
A single, rather than a multiple value operator was used.
Second subquery found on the right instead of the left side of the operator.
A correlated subquery is evaluated _____ for each row processed by the parent statement. Mark
for Review
(1) Points
ONCE*
EVERY TIME
COMPLETELY
Which of the following is a valid reason why the query below will not execute successfully?
SELECT employee_id, last_name, salary
FROM employees
WHERE department_id =
(SELECT department_id FROM employees WHERE last_name like '%u%');
The greater than operator is not valid.
Second subquery found on the right instead of the left side of the operator.
First subquery not enclosed in parentheses.
A single, rather than a multiple value operator was used.
using candidate row value, and _______ values from the inner query to qualify or disqualify the
candidate row.
ROLLUP; GRANT; DROP
DELETE; UPDATE; INSERT
GET; EXECUTE; USE (*)
CREATE; EXECUTE; USE
2- Which operator can be used with subqueries that return only one row?
ANY
ALL
IN
LIKE (*)
3- Subqueries can only be placed in the WHERE clause. True or False?
True
False (*)
