Test Your Oracle GROUP RANK Knowledge with This Engaging SQL Quiz

Progress

True / False

In Oracle, the RANK function is used to assign a rank to each row within a partition of a result set.

True False

The RANK function assigns a rank to each row within a partition of a result set, with the same rank for rows with equal values.

True / False

The DENSE_RANK function in Oracle assigns unique ranks without gaps between the ranks.

True False

The DENSE_RANK function assigns ranks to rows within a partition without gaps between the rank values.

True / False

In Oracle, the RANK function can be used without the OVER clause.

True False

The RANK function must be used with the OVER clause, which defines the partitioning and ordering of rows.

True / False

In Oracle, you can use the RANK function to rank rows within each group created by the GROUP BY clause.

True False

The RANK function can be used with the PARTITION BY clause to rank rows within each group created by the GROUP BY clause.

True / False

The RANK function in Oracle assigns the same rank to rows with equal values, but leaves gaps in the ranking sequence.

True False

The RANK function assigns the same rank to rows with equal values and leaves gaps in the ranking sequence for ties.

True / False

In Oracle, the NTILE function can be used to divide rows into a specified number of roughly equal groups.

True False

The NTILE function divides rows into a specified number of roughly equal groups, assigning a unique group number to each row.

True / False

In Oracle, the RANK function can be used in a WHERE clause to filter rows based on their rank.

True False

The RANK function cannot be used directly in a WHERE clause. Instead, it must be used in a subquery or common table expression (CTE), and then filtered in an outer query.

True / False

The ROW_NUMBER function in Oracle assigns a unique sequential integer to rows within a partition, without regard to ties.

True False

The ROW_NUMBER function assigns a unique sequential integer to each row within a partition, even if there are ties.

True / False

In Oracle, you can use window functions like RANK and DENSE_RANK in combination with analytic functions to perform complex calculations over partitions of data.

True False

Window functions like RANK and DENSE_RANK can be used alongside analytic functions to perform complex calculations over partitions of data.

Q10

True / False

The Oracle Certified Professional (OCP) exam includes knowledge on using ranking functions like RANK, DENSE_RANK, and ROW_NUMBER effectively, understanding their syntax, and optimizing their performance in SQL queries.

True False

The OCP certification covers advanced topics, including the effective use of ranking functions, understanding their syntax, and optimizing their performance in SQL queries.

Q11

Single Choice

Which Oracle SQL function is used to assign a unique rank to each distinct value in a result set, based on the ordering of a specified column?

RANK ROW_NUMBER DENSE_RANKNTILE

The RANK function in Oracle assigns a unique rank to each distinct value in the result set, based on the specified column's order. It skips ranks if there are ties.

Q12

Single Choice

In Oracle, which of the following functions is most suitable to rank rows within a group and allows for ranking with gaps?

DENSE_RANK ROW_NUMBER RANKCOUNT

The RANK function allows for ranking rows within a group, introducing gaps if there are ties.

Q13

Single Choice

What is the correct syntax for using the RANK function in Oracle to rank rows based on the salary column?

SELECT RANK() OVER (ORDER BY salary) FROM employees; SELECT RANK BY salary FROM employees; SELECT RANK(salary) FROM employees;SELECT RANK ORDER BY salary FROM employees;

The correct syntax for using the RANK function is RANK() OVER (ORDER BY column_name).

Q14

Single Choice

Which Oracle SQL function can be used in conjunction with PARTITION BY to rank rows within each group?

DENSE_RANK RANK NTILEROW_NUMBER

The RANK function can be used with PARTITION BY to rank rows within each group defined by the partition.

Q15

Single Choice

Consider the following Oracle SQL query:What does the query achieve?

SQL Code

SELECT employee_id, department_id,
 RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS emp_rank
FROM employees;

Ranks employees within each department by their hire date. Ranks employees across all departments by their salary. Ranks employees within each department by their salary.Ranks employees within each department by their employee ID.

The query partitions the data by department_id and ranks employees within each department based on their salary in descending order.

Q16

Single Choice

Given the Oracle SQL code:Which employees will have the same rank within a department?

SQL Code

SELECT employee_id, department_id,
 RANK() OVER (PARTITION BY department_id ORDER BY hire_date) AS hire_rank
FROM employees;

Employees with the same employee_id Employees with the same hire_date Employees with the same department_idEmployees with the same salary

The RANK function assigns the same rank to rows with the same hire_date within each department.

Q17

Single Choice

Consider the Oracle SQL query:What is the difference between salary_rank and dense_salary_rank?

SQL Code

SELECT employee_id,
 RANK() OVER (ORDER BY salary DESC) AS salary_rank,
 DENSE_RANK() OVER (ORDER BY salary DESC) AS dense_salary_rank
FROM employees;

RANK and DENSE_RANK always return the same result. RANK may leave gaps in the rankings if there are ties, whereas DENSE_RANK does not. DENSE_RANK may leave gaps in the rankings if there are ties, whereas RANK does not.RANK does not consider ties, while DENSE_RANK does.

RANK leaves gaps in the ranking sequence if there are ties, while DENSE_RANK does not skip any ranks.

Q18

Single Choice

In Oracle SQL, which ranking function should be used if you want to ensure that no gaps appear in the rank sequence even when there are ties?

RANK ROW_NUMBER DENSE_RANKNTILE

The DENSE_RANK function ensures that there are no gaps in the ranking sequence, even when there are ties.

Q19

Single Choice

Which of the following Oracle SQL statements correctly ranks employees within departments by salary, ensuring no gaps in ranking?

SELECT DENSE_RANK() OVER (ORDER BY salary DESC) FROM employees; SELECT DENSE_RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) FROM employees; SELECT RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) FROM employees;SELECT DENSE_RANK BY department_id ORDER BY salary DESC FROM employees;

This statement ranks employees within each department by salary, ensuring no gaps in ranking due to ties.

Q20

Single Choice

You have a dataset in an Oracle database where you want to assign ranks to employees based on their salary, but you want to ensure that employees with the same salary receive the same rank, and that there are no gaps in the rank sequence. Which SQL query achieves this?

SELECT RANK() OVER (ORDER BY salary DESC) FROM employees; SELECT DENSE_RANK() OVER (ORDER BY salary DESC) FROM employees; SELECT NTILE(100) OVER (ORDER BY salary DESC) FROM employees;SELECT ROW_NUMBER() OVER (ORDER BY salary DESC) FROM employees;

The DENSE_RANK function is used to assign ranks without leaving gaps when there are ties, making it the correct choice for the specified requirement.

Q21

Multiple Choice

Which SQL code snippet demonstrates using the `RANK` function to assign ranks within a department based on salary?

SQL Code

SELECT employee_id, department_id, salary,
RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank
FROM employees;

SELECT employee_id, department_id, salary, RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank FROM employees; SELECT employee_id, department_id, salary, RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank FROM employees; SELECT employee_id, department_id, salary, RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank FROM employees;SELECT employee_id, department_id, salary FROM employees ORDER BY salary DESC;

Options A, B, and C correctly demonstrate the use of the `RANK` function to assign ranks within each department based on descending salary. Option D is incorrect because it does not use the `RANK` function.

Q22

Multiple Choice

Which SQL code snippet demonstrates using the `DENSE_RANK` function to handle ranking when duplicate values exist?

SQL Code

SELECT employee_id, department_id, salary,
DENSE_RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_dense_rank
FROM employees;

SELECT employee_id, department_id, salary, DENSE_RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_dense_rank FROM employees; SELECT employee_id, department_id, salary, DENSE_RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_dense_rank FROM employees; SELECT employee_id, department_id, salary, DENSE_RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_dense_rank FROM employees;SELECT employee_id, department_id, salary FROM employees ORDER BY salary DESC;

Options A, B, and C correctly demonstrate the use of the `DENSE_RANK` function to handle ranking where duplicate values exist, assigning consecutive ranks without gaps. Option D is incorrect because it does not use the `DENSE_RANK` function.

Q23

Multiple Choice

Which SQL code snippet demonstrates using the `ROW_NUMBER` function to assign unique row numbers within each department?

SQL Code

SELECT employee_id, department_id, salary,
ROW_NUMBER() OVER (PARTITION BY department_id ORDER BY salary DESC) AS row_num
FROM employees;

SELECT employee_id, department_id, salary, ROW_NUMBER() OVER (PARTITION BY department_id ORDER BY salary DESC) AS row_num FROM employees; SELECT employee_id, department_id, salary, ROW_NUMBER() OVER (PARTITION BY department_id ORDER BY salary DESC) AS row_num FROM employees; SELECT employee_id, department_id, salary, ROW_NUMBER() OVER (PARTITION BY department_id ORDER BY salary DESC) AS row_num FROM employees;SELECT employee_id, department_id, salary FROM employees ORDER BY salary DESC;

Options A, B, and C correctly demonstrate the use of the `ROW_NUMBER` function to assign unique row numbers within each department based on descending salary. Option D is incorrect because it does not use the `ROW_NUMBER` function.

Q24

Multiple Choice

Which SQL code snippet demonstrates using `RANK` in conjunction with `GROUP BY` to rank departments by their average salary?

SQL Code

SELECT department_id, AVG(salary) AS avg_salary,
RANK() OVER (ORDER BY AVG(salary) DESC) AS dept_rank
FROM employees
GROUP BY department_id;

SELECT department_id, AVG(salary) AS avg_salary, RANK() OVER (ORDER BY AVG(salary) DESC) AS dept_rank FROM employees GROUP BY department_id; SELECT department_id, AVG(salary) AS avg_salary, RANK() OVER (ORDER BY AVG(salary) DESC) AS dept_rank FROM employees GROUP BY department_id; SELECT department_id, AVG(salary) AS avg_salary, RANK() OVER (ORDER BY AVG(salary) DESC) AS dept_rank FROM employees GROUP BY department_id;SELECT department_id, AVG(salary) AS avg_salary FROM employees GROUP BY department_id;

Options A, B, and C correctly demonstrate the use of `RANK` in conjunction with `GROUP BY` to rank departments based on their average salary. Option D is incorrect because it does not use the `RANK` function.

Q25

Multiple Choice

Which SQL code snippet demonstrates using `NTILE` to divide employees into quartiles based on their salary?

SQL Code

SELECT employee_id, salary,
NTILE(4) OVER (ORDER BY salary DESC) AS salary_quartile
FROM employees;

SELECT employee_id, salary, NTILE(4) OVER (ORDER BY salary DESC) AS salary_quartile FROM employees; SELECT employee_id, salary, NTILE(4) OVER (ORDER BY salary DESC) AS salary_quartile FROM employees; SELECT employee_id, salary, NTILE(4) OVER (ORDER BY salary DESC) AS salary_quartile FROM employees;SELECT employee_id, salary FROM employees ORDER BY salary DESC;

Options A, B, and C correctly demonstrate the use of the `NTILE` function to divide employees into quartiles based on descending salary. Option D is incorrect because it does not use the `NTILE` function.

Q26

Multiple Choice

Which SQL code snippet demonstrates advanced use of the `RANK` function to rank employees within each department based on their performance score?

SQL Code

SELECT employee_id, department_id, performance_score,
RANK() OVER (PARTITION BY department_id ORDER BY performance_score DESC) AS performance_rank
FROM employees;

SELECT employee_id, department_id, performance_score, RANK() OVER (PARTITION BY department_id ORDER BY performance_score DESC) AS performance_rank FROM employees; SELECT employee_id, department_id, performance_score, RANK() OVER (PARTITION BY department_id ORDER BY performance_score DESC) AS performance_rank FROM employees; SELECT employee_id, department_id, performance_score, RANK() OVER (PARTITION BY department_id ORDER BY performance_score DESC) AS performance_rank FROM employees;SELECT employee_id, department_id, performance_score FROM employees ORDER BY performance_score DESC;

Options A, B, and C correctly demonstrate the advanced use of the `RANK` function to rank employees within each department based on performance. Option D is incorrect because it does not use the `RANK` function.

Q27

Multiple Choice

Which SQL code snippet demonstrates advanced use of the `DENSE_RANK` function in a nested subquery to rank employees by hire date within their department?

SQL Code

SELECT employee_id, department_id, hire_date
FROM (SELECT employee_id, department_id, hire_date,
DENSE_RANK() OVER (PARTITION BY department_id ORDER BY hire_date) AS hire_rank
FROM employees) subquery
WHERE hire_rank = 1;

SELECT employee_id, department_id, hire_date FROM (SELECT employee_id, department_id, hire_date, DENSE_RANK() OVER (PARTITION BY department_id ORDER BY hire_date) AS hire_rank FROM employees) subquery WHERE hire_rank = 1; SELECT employee_id, department_id, hire_date FROM (SELECT employee_id, department_id, hire_date, DENSE_RANK() OVER (PARTITION BY department_id ORDER BY hire_date) AS hire_rank FROM employees) subquery WHERE hire_rank = 1; SELECT employee_id, department_id, hire_date FROM (SELECT employee_id, department_id, hire_date, DENSE_RANK() OVER (PARTITION BY department_id ORDER BY hire_date) AS hire_rank FROM employees) subquery WHERE hire_rank = 1;SELECT employee_id, department_id, hire_date FROM employees ORDER BY hire_date;

Options A, B, and C correctly demonstrate the advanced use of `DENSE_RANK` within a subquery to rank employees by hire date. Option D is incorrect because it does not use the `DENSE_RANK` function.

Q28

Multiple Choice

Which SQL code snippet demonstrates certification-level use of the `RANK` function to determine the top 3 highest-paid employees in each department?

SQL Code

SELECT employee_id, department_id, salary
FROM (SELECT employee_id, department_id, salary,
RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank
FROM employees) subquery
WHERE salary_rank <= 3;

SELECT employee_id, department_id, salary FROM (SELECT employee_id, department_id, salary, RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank FROM employees) subquery WHERE salary_rank <= 3; SELECT employee_id, department_id, salary FROM (SELECT employee_id, department_id, salary, RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank FROM employees) subquery WHERE salary_rank <= 3; SELECT employee_id, department_id, salary FROM (SELECT employee_id, department_id, salary, RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) AS salary_rank FROM employees) subquery WHERE salary_rank <= 3;SELECT employee_id, department_id, salary FROM employees ORDER BY salary DESC;

Options A, B, and C correctly demonstrate the certification-level use of `RANK` to identify the top 3 highest-paid employees in each department. Option D is incorrect because it does not use the `RANK` function.

Q29

Multiple Choice

Which SQL code snippet demonstrates certification-level use of the `RANK` function combined with a window function to calculate cumulative salary?

SQL Code

SELECT employee_id, department_id, salary,
SUM(salary) OVER (ORDER BY RANK() OVER (PARTITION BY department_id ORDER BY salary DESC)) AS cumulative_salary
FROM employees;

SELECT employee_id, department_id, salary, SUM(salary) OVER (ORDER BY RANK() OVER (PARTITION BY department_id ORDER BY salary DESC)) AS cumulative_salary FROM employees; SELECT employee_id, department_id, salary, SUM(salary) OVER (ORDER BY RANK() OVER (PARTITION BY department_id ORDER BY salary DESC)) AS cumulative_salary FROM employees; SELECT employee_id, department_id, salary, SUM(salary) OVER (ORDER BY RANK() OVER (PARTITION BY department_id ORDER BY salary DESC)) AS cumulative_salary FROM employees;SELECT employee_id, department_id, salary FROM employees ORDER BY salary DESC;

Options A, B, and C correctly demonstrate the certification-level use of `RANK` combined with a window function to calculate cumulative salary. Option D is incorrect because it does not use the `RANK` function.

Q30

Multiple Choice

Which SQL code snippet demonstrates certification-level use of the `DENSE_RANK` function to identify the highest-performing department?

SQL Code

SELECT department_id, performance_score,
DENSE_RANK() OVER (ORDER BY AVG(performance_score) DESC) AS dept_rank
FROM employees
GROUP BY department_id
HAVING DENSE_RANK() = 1;

SELECT department_id, performance_score, DENSE_RANK() OVER (ORDER BY AVG(performance_score) DESC) AS dept_rank FROM employees GROUP BY department_id HAVING DENSE_RANK() = 1; SELECT department_id, performance_score, DENSE_RANK() OVER (ORDER BY AVG(performance_score) DESC) AS dept_rank FROM employees GROUP BY department_id HAVING DENSE_RANK() = 1; SELECT department_id, performance_score, DENSE_RANK() OVER (ORDER BY AVG(performance_score) DESC) AS dept_rank FROM employees GROUP BY department_id HAVING DENSE_RANK() = 1;SELECT department_id, performance_score FROM employees GROUP BY department_id ORDER BY AVG(performance_score) DESC;

Options A, B, and C correctly demonstrate the certification-level use of `DENSE_RANK` to identify the highest-performing department based on average performance score. Option D is incorrect because it does not use the `DENSE_RANK` function.

Oracle Database Quiz Questions