Why views are needed in SQL - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a simple view that shows all employees.

SQL

CREATE VIEW employee_view AS SELECT [1] FROM employees;

Drag options to blanks, or click blank then click option'

Aname

Bid

Csalary

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using a specific column name instead of selecting all columns.

Leaving the SELECT statement empty.

The * selects all columns from the employees table to include in the view.

2fill in blank

medium

Complete the code to select only the name and salary columns from the view.

SQL

SELECT [1] FROM employee_view;

Drag options to blanks, or click blank then click option'

Aname, salary

Bid, department

Csalary, id

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Selecting all columns (*) instead of specific ones.

Mixing up column names.

To get only the name and salary columns, list them separated by a comma.

3fill in blank

hard

Fix the error in the view creation by completing the code correctly.

SQL

CREATE VIEW [1] AS SELECT id, name FROM employees;

Drag options to blanks, or click blank then click option'

Aview_employee

Bemployee_view

Cemployees_view

Demployee

Attempts:

3 left

💡 Hint

Common Mistakes

Using table names instead of view names.

Using ambiguous or unclear names.

The view name should be employee_view to follow naming conventions and clarity.

4fill in blank

hard

Fill both blanks to create a view that shows only employees with salary greater than 50000.

SQL

CREATE VIEW [1] AS SELECT name, salary FROM employees WHERE salary [2] 50000;

Drag options to blanks, or click blank then click option'

Ahigh_salary_employees

B>

C<

Demployee_salaries

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong comparison operator.

Choosing unclear view names.

The view name high_salary_employees describes the content, and the operator > filters salaries greater than 50000.

5fill in blank

hard

Fill all three blanks to create a view that shows employee names in uppercase and their departments, only for departments with more than 10 employees.

SQL

CREATE VIEW [1] AS SELECT [2] AS name_upper, department FROM employees WHERE department IN (SELECT department FROM employees GROUP BY department HAVING COUNT(*) [3] 10);

Drag options to blanks, or click blank then click option'

Adept_large_employees

BUPPER(name)

C>

DLOWER(name)

Attempts:

3 left

💡 Hint

Common Mistakes

Using LOWER instead of UPPER for name conversion.

Using wrong comparison operator in HAVING clause.

Choosing unclear or unrelated view names.

The view name dept_large_employees fits the purpose. UPPER(name) converts names to uppercase. The operator > filters departments with more than 10 employees.