DBMS LAb Quiz II

STUDENTS (student_code, first_name, last_name, email, phone_no, date_of_birth, honours_subject, percentage_of_marks);

Which of the following query would display all the students whose first name starts with the character ‘A’?A

• select first_name from students where first_name like ‘A%’;

• select first_name from students where first_name like ‘%A’;

• select first_name from students where first_name like ‘%A%’;

• select first_name from students where first_name like ‘A’; 

With SQL, how can you return the number of not null records in the “Persons” table?

• SELECT COUNT() FROM Persons

• SELECT COLUMNS() FROM Persons

• SELECT COLUMNS(*) FROM Persons

• SELECT COUNT(*) FROM Persons

You have a "Products" relation that contains information about products, including their prices. You want to find the products with a price greater than $100. What relational algebra operation would you use?

• SELECT

•   PROJECT

• JOIN

• DIFFERENCE

You have two relations, "Employees" and "Departments." The "Employees" relation contains employee information, and the "Departments" relation contains department information. You want to find all employees in the "HR" department. What relational algebra operation would you use

• SELECT

• PROJECT

• JOIN

• INTERSECT

SQL query to find all the cities whose humidity is 95.

• SELECT city WHERE humidity = 95

• SELECT city FROM weather WHERE humidity = 95

• SELECT city FROM weather

• SELECT humidity = 89 FROM weather

Which of the following statement is true?

• DELETE does not free the space containing the table and TRUNCATE free the space containing the table

• Both DELETE and TRUNCATE free the space containing the table

• Both DELETE and TRUNCATE does not free the space containing the table

• DELETE free the space containing the table and TRUNCATE does not free the space containing the table

1.       A database contains a table named employees with columns employee_id, employee_name, and salary. A user initiates a transaction to increase the salary of all employees by 10%. Which SQL statement should be used to update the salary within the transaction?

• UPDATE employees SET salary = salary * 1.10;

• MODIFY employees SET salary = salary * 1.10;

• ALTER employees SET salary = salary * 1.10;

• CHANGE employees SET salary = salary * 1.10;

A user initiates a transaction to insert a new customer record into a table named customers. The customer's information includes customer_id, customer_name, and email. Which SQL statement should be used to insert the new record within the transaction?

• ADD RECORD INTO customers (101, 'John Doe', '[e-mail]');

• CREATE RECORD INTO customers (101, 'John Doe', '[e-mail]');

• ADD INTO customers (customer_id, customer_name, email) VALUES (101, 'John Doe', '[e-mail]');

• INSERT INTO customers VALUES (101, 'John Doe', '[e-mail]');

Find all the cities with temperature, condition and humidity whose humidity is in the range of 63 to 79.

• SELECT * FROM weather WHERE humidity IN (63 to 79)

• SELECT * FROM weather WHERE humidity NOT IN (63 AND 79)

• SELECT * FROM weather WHERE humidity BETWEEN 63 AND 79

• SELECT * FROM weather WHERE humidity NOT BETWEEN 63 AND 79

A database contains a table named customers with columns customer_id, customer_name, and total_purchase. A user initiates a transaction to increase the total purchase amount by 5% for a specific customer with customer_id = 105. Which SQL statement should be used to perform this update within the transaction?

• CHANGE customers SET total_purchase = total_purchase * 1.05 WHERE customer_id = 105;

• ALTER customers SET total_purchase = total_purchase * 1.05 WHERE customer_id = 105;

• MODIFY customers SET total_purchase = total_purchase * 1.05 WHERE customer_id = 105;

• UPDATE customers SET total_purchase = total_purchase * 1.05 WHERE customer_id = 105;