Test Your Oracle ORDER BY Clause Knowledge

Progress

True / False

The ORDER BY clause in Oracle is used to sort the result set of a query.

True False

The ORDER BY clause sorts the rows returned by a query based on one or more columns.

True / False

In Oracle, the ORDER BY clause must be placed before the WHERE clause in a query.

True False

The ORDER BY clause must be placed after the WHERE clause and any GROUP BY or HAVING clauses.

True / False

By default, the ORDER BY clause in Oracle sorts the result set in ascending order.

True False

If no sort direction is specified, ORDER BY defaults to ascending order (ASC).

True / False

In Oracle, you can use the ORDER BY clause to sort results by multiple columns.

True False

You can specify multiple columns in the ORDER BY clause, and the result set will be sorted by each column in the order they are listed.

True / False

In Oracle, the ORDER BY clause can sort results in descending order using the DESC keyword.

True False

Adding the DESC keyword after a column in the ORDER BY clause sorts the results in descending order.

True / False

In Oracle, you can use column aliases in the ORDER BY clause.

True False

Column aliases defined in the SELECT statement can be used in the ORDER BY clause to sort the result set.

True / False

In Oracle, you can use the ORDER BY clause with a subquery to sort the subquery's results.

True False

The ORDER BY clause can be used within a subquery to sort the results of the subquery before they are used by the main query.

True / False

In Oracle, the ORDER BY clause can include expressions and functions to define custom sorting criteria.

True False

The ORDER BY clause can use expressions and functions to sort the results based on complex criteria.

True / False

In Oracle, using ORDER BY in a query with a large dataset always improves performance.

True False

Sorting a large dataset with ORDER BY can be resource-intensive and may impact performance. Proper indexing and query optimization are necessary to mitigate performance issues.

Q10

True / False

The Oracle Certified Professional (OCP) exam includes knowledge on optimizing the ORDER BY clause for performance and understanding its interaction with indexes and execution plans.

True False

The OCP certification covers advanced topics, including optimizing the ORDER BY clause for performance and understanding how it interacts with indexes and execution plans, reflecting a deep understanding of Oracle SQL.

Q11

Single Choice

What is the purpose of the ORDER BY clause in an Oracle SQL query?

To filter rows based on a condition To sort the result set in ascending or descending order To group rows by a specific columnTo update rows in a table

The ORDER BY clause in Oracle is used to sort the rows in the result set based on one or more columns, either in ascending (default) or descending order.

Q12

Single Choice

Consider the following Oracle SQL query:What will this query do?

SQL Code

SELECT * FROM employees ORDER BY last_name;

It will return all rows sorted by first_name It will return all rows sorted by last_name in ascending order It will return all rows sorted by last_name in descending orderIt will raise an error because the sort order is not specified

The ORDER BY last_name clause sorts the result set by the last_name column in ascending order by default.

Q13

Single Choice

Which of the following is the default sort order used by the ORDER BY clause in Oracle?

Ascending Descending RandomGrouped

In Oracle, if no sort order is specified, the ORDER BY clause sorts the result set in ascending order by default.

Q14

Single Choice

Consider the following Oracle SQL query:What will this query return?

SQL Code

SELECT * FROM products ORDER BY price DESC;

All rows sorted by price in ascending order All rows sorted by product_name in descending order All rows sorted by price in descending orderOnly rows where price is greater than 1000

The ORDER BY price DESC clause sorts the rows in the products table by price in descending order.

Q15

Single Choice

What is the effect of using multiple columns in the ORDER BY clause in an Oracle SQL query?

The query will raise an error The result set will be sorted by the first column, then by the second column if there are ties The result set will only be sorted by the last columnThe query will ignore the ORDER BY clause

When multiple columns are used in the ORDER BY clause, Oracle sorts the result set by the first column and then sorts by the second column if there are rows with the same value in the first column.

Q16

Single Choice

Consider the following Oracle SQL query:How will the result set be sorted?

SQL Code

SELECT * FROM employees ORDER BY department_id, salary DESC;

By salary in descending order only By department_id in ascending order, then by salary in descending order within each department By department_id and salary both in descending orderBy department_id and salary both in ascending order

This query first sorts the result set by department_id in ascending order, then by salary in descending order within each department.

Q17

Single Choice

What happens when you use ORDER BY on a column that contains NULL values in Oracle?

NULL values are sorted as the smallest values NULL values are sorted as the largest values NULL values are excluded from the result setThe query raises an error

In Oracle, NULL values are considered the smallest when sorting in ascending order, so they appear first in the result set. Conversely, in descending order, they appear last.

Q18

Single Choice

Consider the following Oracle SQL query:What does the NULLS LAST clause do in this query?

SQL Code

SELECT * FROM orders ORDER BY order_date NULLS LAST;

It places rows with NULL in order_date at the beginning of the result set It places rows with NULL in order_date at the end of the result set It excludes rows with NULL in order_date from the result setIt raises an error because NULLS LAST is not valid

The NULLS LAST clause in Oracle forces rows with NULL values in order_date to appear at the end of the result set when sorting.

Q19

Single Choice

What will be the result of executing the following Oracle SQL query?

SQL Code

SELECT * FROM employees ORDER BY hire_date, salary;

Employees sorted by salary only Employees sorted by hire_date in descending order and then by salary in ascending order Employees sorted by hire_date in ascending order and then by salary in ascending orderEmployees sorted by hire_date only

The ORDER BY hire_date, salary clause sorts the result set first by hire_date in ascending order (default), and then by salary in ascending order for rows with the same hire_date.

Q20

Single Choice

In an Oracle certification exam, you encounter the following SQL statement:What does this query return?

SQL Code

SELECT department_id, COUNT(*) FROM employees GROUP BY department_id ORDER BY COUNT(*) DESC, department_id ASC;

A count of employees in each department, sorted by department ID in ascending order A count of employees in each department, sorted by the count in descending order and then by department ID in ascending order All employees sorted by department IDA list of departments without employee counts

This query groups employees by department_id and counts them, then sorts the result first by the employee count in descending order and, for ties, by department_id in ascending order.

Q21

Multiple Choice

Which SQL code snippet correctly uses the ORDER BY clause to sort employees by their last names in ascending order in Oracle?

SQL Code

SELECT *
FROM employees
ORDER BY last_name ASC;

SELECT *
FROM employees
ORDER BY last_name DESC;

SELECT last_name, first_name
FROM employees
ORDER BY last_name;

SELECT * FROM employees ORDER BY last_name ASC; SELECT * FROM employees ORDER BY last_name DESC; SELECT last_name, first_name FROM employees ORDER BY last_name;SELECT * FROM employees ORDER BY first_name ASC;

Options A and C correctly sort employees by their last names in ascending order. Option B sorts in descending order.

Q22

Multiple Choice

Which SQL code snippet demonstrates how to use ORDER BY to sort orders by order date in descending order in Oracle?

SQL Code

SELECT *
FROM orders
ORDER BY order_date DESC;

SELECT *
FROM orders
ORDER BY order_date ASC;

SELECT order_id, order_date
FROM orders
ORDER BY order_date DESC;

SELECT * FROM orders ORDER BY order_date DESC; SELECT * FROM orders ORDER BY order_date ASC; SELECT order_id, order_date FROM orders ORDER BY order_date DESC;SELECT * FROM orders ORDER BY order_id DESC;

Options A and C correctly sort orders by order date in descending order. Option B sorts in ascending order.

Q23

Multiple Choice

Which SQL code snippet uses ORDER BY to sort products first by category and then by price in ascending order in Oracle?

SQL Code

SELECT *
FROM products
ORDER BY category_id, price ASC;

SELECT *
FROM products
ORDER BY category_id DESC, price ASC;

SELECT category_id, price
FROM products
ORDER BY category_id, price;

SELECT * FROM products ORDER BY category_id, price ASC; SELECT * FROM products ORDER BY category_id DESC, price ASC; SELECT category_id, price FROM products ORDER BY category_id, price;SELECT * FROM products ORDER BY price ASC;

Options A and C correctly sort products first by category and then by price in ascending order. Option B sorts categories in descending order.

Q24

Multiple Choice

Which SQL code snippet demonstrates how to use ORDER BY to sort customers by their city in alphabetical order in Oracle?

SQL Code

SELECT *
FROM customers
ORDER BY city ASC;

SELECT *
FROM customers
ORDER BY city DESC;

SELECT customer_id, city
FROM customers
ORDER BY city;

SELECT * FROM customers ORDER BY city ASC; SELECT * FROM customers ORDER BY city DESC; SELECT customer_id, city FROM customers ORDER BY city;SELECT * FROM customers ORDER BY customer_id ASC;

Options A and C correctly sort customers by city in alphabetical order. Option B sorts in reverse alphabetical order.

Q25

Multiple Choice

Which SQL code snippet uses ORDER BY to sort the sales data by amount in descending order and then by sale date in ascending order in Oracle?

SQL Code

SELECT *
FROM sales
ORDER BY amount DESC, sale_date ASC;

SELECT *
FROM sales
ORDER BY amount ASC, sale_date DESC;

SELECT amount, sale_date
FROM sales
ORDER BY amount DESC, sale_date ASC;

SELECT * FROM sales ORDER BY amount DESC, sale_date ASC; SELECT * FROM sales ORDER BY amount ASC, sale_date DESC; SELECT amount, sale_date FROM sales ORDER BY amount DESC, sale_date ASC;SELECT * FROM sales ORDER BY sale_date ASC, amount DESC;

Options A and C correctly sort sales data by amount in descending order and then by sale date in ascending order. Option B sorts by amount in ascending order.

Q26

Multiple Choice

Which SQL code snippet demonstrates advanced use of ORDER BY to sort employees by department and within each department by hire date in ascending order in Oracle?

SQL Code

SELECT *
FROM employees
ORDER BY department_id, hire_date ASC;

SELECT *
FROM employees
ORDER BY department_id DESC, hire_date ASC;

SELECT department_id, hire_date
FROM employees
ORDER BY department_id, hire_date;

SELECT * FROM employees ORDER BY department_id, hire_date ASC; SELECT * FROM employees ORDER BY department_id DESC, hire_date ASC; SELECT department_id, hire_date FROM employees ORDER BY department_id, hire_date;SELECT * FROM employees ORDER BY hire_date ASC, department_id;

Options A and C correctly sort employees by department and within each department by hire date in ascending order. Option B sorts departments in descending order.

Q27

Multiple Choice

Which SQL code snippet uses ORDER BY to sort orders by customer ID in ascending order and then by order total in descending order in Oracle?

SQL Code

SELECT *
FROM orders
ORDER BY customer_id ASC, order_total DESC;

SELECT *
FROM orders
ORDER BY customer_id DESC, order_total ASC;

SELECT customer_id, order_total
FROM orders
ORDER BY customer_id ASC, order_total DESC;

SELECT * FROM orders ORDER BY customer_id ASC, order_total DESC; SELECT * FROM orders ORDER BY customer_id DESC, order_total ASC; SELECT customer_id, order_total FROM orders ORDER BY customer_id ASC, order_total DESC;SELECT * FROM orders ORDER BY order_total DESC, customer_id ASC;

Options A and C correctly sort orders by customer ID in ascending order and then by order total in descending order. Option B sorts by customer ID in descending order.

Q28

Multiple Choice

Which SQL code snippet demonstrates advanced use of ORDER BY to sort products by category in descending order and then by product name in ascending order in Oracle?

SQL Code

SELECT *
FROM products
ORDER BY category_id DESC, product_name ASC;

SELECT *
FROM products
ORDER BY category_id ASC, product_name DESC;

SELECT category_id, product_name
FROM products
ORDER BY category_id DESC, product_name ASC;

SELECT * FROM products ORDER BY category_id DESC, product_name ASC; SELECT * FROM products ORDER BY category_id ASC, product_name DESC; SELECT category_id, product_name FROM products ORDER BY category_id DESC, product_name ASC;SELECT * FROM products ORDER BY product_name ASC, category_id DESC;

Options A and C correctly sort products by category in descending order and then by product name in ascending order. Option B sorts categories in ascending order.

Q29

Multiple Choice

Which SQL code snippet uses ORDER BY to retrieve the top 10 highest paid employees sorted by salary in descending order in Oracle?

SQL Code

SELECT *
FROM employees
ORDER BY salary DESC
FETCH FIRST 10 ROWS ONLY;

SELECT *
FROM employees
ORDER BY salary ASC
FETCH FIRST 10 ROWS ONLY;

SELECT salary, first_name
FROM employees
ORDER BY salary DESC
FETCH FIRST 10 ROWS ONLY;

SELECT * FROM employees ORDER BY salary DESC FETCH FIRST 10 ROWS ONLY; SELECT * FROM employees ORDER BY salary ASC FETCH FIRST 10 ROWS ONLY; SELECT salary, first_name FROM employees ORDER BY salary DESC FETCH FIRST 10 ROWS ONLY;SELECT * FROM employees ORDER BY first_name DESC FETCH FIRST 10 ROWS ONLY;

Options A and C correctly retrieve the top 10 highest paid employees sorted by salary in descending order. Option B sorts in ascending order.

Q30

Multiple Choice

Which SQL code snippet demonstrates the certification-level use of ORDER BY to retrieve products sorted by their sales rank in ascending order, then by name in descending order in Oracle?

SQL Code

SELECT *
FROM products
ORDER BY sales_rank ASC, product_name DESC;

SELECT *
FROM products
ORDER BY sales_rank DESC, product_name ASC;

SELECT sales_rank, product_name
FROM products
ORDER BY sales_rank ASC, product_name DESC;

SELECT * FROM products ORDER BY sales_rank ASC, product_name DESC; SELECT * FROM products ORDER BY sales_rank DESC, product_name ASC; SELECT sales_rank, product_name FROM products ORDER BY sales_rank ASC, product_name DESC;SELECT * FROM products ORDER BY product_name DESC, sales_rank ASC;

Options A and C correctly retrieve products sorted by sales rank in ascending order and by name in descending order. Option B sorts sales rank in descending order.

Oracle Database Quiz Questions