SQL Query Quiz

Write a SQL query to select all columns from a table named 'students'.

• SELECT columns FROM students;

• SELECT * FROM student;

• SELECT * FROM table students;

• SELECT * FROM students;

How can you update the 'age' column in a table named 'employees' to set all values to 30?

• UPDATE employees SET age = 30

• UPDATE employees SET age = '30'

• ALTER TABLE employees SET age = 30

• SET age = 30 WHERE employees

What is the SQL query to delete all records from a table named 'orders' where the 'status' is 'cancelled'?

• DROP FROM orders WHERE status = 'cancelled';

• REMOVE FROM orders WHERE status = 'cancelled';

• DELETE FROM orders WHERE status = 'cancelled';

• DELETE * FROM orders WHERE status = 'cancelled';

Create a SQL query to create a table named 'products' with columns 'id' (int), 'name' (varchar), and 'price' (decimal).

• CREATE TABLE products (id INT, name VARCHAR(255), price DECIMAL(10,2));

• CREATE TABLE products (id INT, name VARCHAR(255), price VARCHAR);

• CREATE TABLE products (id INT, name DECIMAL, price VARCHAR(255));

• CREATE TABLE products (id VARCHAR, name INT, price DECIMAL(10,2));

How can you add a new column 'address' (varchar) to an existing table named 'customers'?

• CREATE NEW COLUMN address IN customers

• ALTER TABLE customers ADD address VARCHAR;

• ADD COLUMN address VARCHAR TO customers

• UPDATE customers SET address = 'New Address'

What is the SQL query to drop a table named 'inventory' from the database?

• DROP TABLE inventory;

• DELETE TABLE inventory;

• DROP DATABASE inventory;

• REMOVE TABLE inventory;

Write a SQL query to select the 'name' and 'salary' columns from a table named 'employees' where 'department' is 'IT'.

• SELECT name, salary FROM employees WHERE department = 'IT';

• SELECT name, salary FROM employees WHERE department = 'Marketing';

• SELECT name, salary FROM employees WHERE department = 'Finance';

• SELECT name, salary FROM employees WHERE department = 'HR';

Update the 'quantity' column in a table named 'stock' to double the existing values.

• ALTER stock MODIFY quantity = quantity * 2;

• UPDATE stock SET quantity = quantity + 2;

• DELETE FROM stock WHERE quantity = quantity * 2;

• UPDATE stock SET quantity = quantity * 2;

Delete all records from a table named 'messages' where the 'timestamp' is older than one year.

• DELETE FROM messages WHERE timestamp > NOW() - INTERVAL 1 YEAR;

• DELETE * FROM messages WHERE timestamp < NOW() - INTERVAL 1 YEAR;

• DELETE FROM messages WHERE timestamp < NOW() - INTERVAL 1 YEAR;

• DELETE FROM messages WHERE timestamp < NOW() + INTERVAL 1 YEAR;

Create a table named 'orders' with columns 'order_id' (int), 'customer_id' (int), and 'order_date' (date).

• CREATE orders (order_id INT, customer_id INT, order_date DATE);

• CREATE TABLE orders (order_id VARCHAR, customer_id INT, order_date DATE);

• CREATE TABLE orders (order_id INT, customer_id INT, order_date DATE);

• CREATE TABLE order (order_id INT, customer_id INT, order_date DATE);