11 MGM Resorts SQL Interview Questions (Updated 2024)

MGM Resorts employees rely on SQL queries to analyze guest behavior data, enabling them to create personalized marketing campaigns that aligns with visitors' preferences. They also use SQL to conduct revenue forecasts for hotel rooms and casino operations, helping the company make informed decisions about pricing and promotions, that is why MGM Resorts evaluates jobseekers with SQL problems in interviews for Data Science, Data Engineering, and Data Analytics jobs.

So, to help you practice, we've curated 11 MGM Resorts International SQL interview questions – able to answer them all?

11 MGM Resorts International SQL Interview Questions

SQL Question 1: Analyze Hotel Room Occupancy

As an analyst working for MGM Resorts, you have been tasked with analyzing room occupancy rates at different MGM hotels. Specifically, you are required to write a SQL query that calculates the average daily amount of occupied rooms for each hotel in 2021. Assume that we consider a room occupied if there is at least one night stay in the room that day.

Below are the tables containing the relevant data:

Sample Input:

Sample Input:

Sample Input:

Answer:

This query builds a dataset that pairs each hotel with every individual day a room was occupied within 2021. It then calculates the average daily occupied rooms by dividing the total count of occupied days by the distinct count of occupied days. The result is the average number of rooms occupied in each hotel per day in 2021.

For more window function practice, try this Uber SQL problem within DataLemur's online SQL code editor:

Get the scoop on MGM Resorts' exciting launch of their mobile sports betting app in Washington D.C.! Following MGM Resorts' updates can give you insight into how they are innovating in the entertainment and gaming industry.

SQL Question 2: Department vs. Company Salary

You're given a table of MGM Resorts employee and department salary data. Write a SQL query to find departments where the departments average salary is higher than the company's average salary.

Solve this question and run your code right in DataLemur's online SQL environment:

The answer is LONG – 30+ lines of SQL. You can find a detailed solution with hints here: Department vs. Company Salary.

SQL Question 3: What distinguishes an inner join from a full outer join?

An inner join only includes rows from both tables that satisfy the join condition, whereas a full outer join includes all rows from both tables, regardless of whether they match the join condition or not.

For example, suppose you had a table of MGM Resorts orders and MGM Resorts customers.

INNER JOIN: When there is a match in the shared key or keys, rows from both tables are retrieved. In this example, an between the and tables would retrieve rows where the in the table matches the in the table.

FULL OUTER JOIN: A retrieves all rows from both tables, regardless of whether there is a match in the shared key or keys. If there is no match, NULL values will be returned for the columns of the non-matching table.

SQL Question 4: Analyzing Monthly Revenue Generation from MGM Resorts' Various Casinos

Assume MGM Resorts operates multiple casinos and you are given the following two tables:

1. - This table contains information about all the casinos owned by MGM Resorts. Each casino is identified by a , and its name and location are recorded.

2. - This table contains all the transactions made at the casinos. Each transaction keeps track of , , the customer's , , and the .

Using these tables, the question is:

"How would you determine the total revenue generated by each casino for each month of a particular year (say, 2022)?"

Example Input:

Example Input:

Answer:

This query returns a list of all the casinos with the total revenue generated by each casino for every month of the year 2022. The result is sorted by month and within each month, by descending order of monthly revenue. The function is used to get the first date of each month. The operation is used to combine rows from and tables. The condition filters for transactions that occurred in 2022. The function is used to total the for each month, for each casino.

SQL Question 5: Can you explain what a cross-join is and the purpose of using them?

A cross-join, also known as a cartesian join, is a JOIN that produces the cross-product of two tables. In a cross-join, each row from the first table is matched with every row from the second table, resulting in a new table with a row for each possible combination of rows from the two input tables.

Let's say you were building a Machine Learning model that attempts to score the probability of a customer purchasing a MGM Resorts product. Before working in Pandas and Tensorflow, you might want to do some Exploratory Data Analysis (EDA) in SQL, and generate all pairs of customers and MGM Resorts products.

Here's a cross-join query you could run:

Cross-joins are useful for generating all possible combinations, but they can also create huge tables if you're not careful. For instance, if you had 10,000 potential customers and MGM Resorts had 500 different product SKUs, the resulting cross-join would have 5 million rows!

SQL Question 6: Find the Average Occupancy Rate Per Hotel

As a Data Analyst for MGM Resorts, you're required to generate reports that provide insights into the business. One report requested by the management is to analyze the occupancy rate of each hotel. In light of this, can you write a SQL query to find the average occupancy rate for each hotel over the last month?

Example Input:

Example Input:

Example Output:

Answer:

In the solution, we used a to combine information from the and tables. The clause filters for records from last month. The function is used to calculate the average. Note that the and columns are cast to for an accurate division result. This is because in SQL, dividing an integer by another integer always results in an integer. We then multiply by 100 to get the average occupancy rate as a percentage. The result is grouped by .

To practice a very similar question try this interactive Facebook Active User Retention Question which is similar for requiring calculation of key metrics over time or this Amazon Average Review Ratings Question which is similar for needing an average calculation for each entity.

SQL Question 7: What is database denormalization, and when is it a good idea to consider it?

Denormalization is the practice of altering a database schema in a way that breaks the normalization rules (1st, 2nd, 3rd normal forms).

A few reasons to denormalize a database:

• Improved performance: Denormalization often reduces the the number of costly join operations that are needed to retrieve data. This is helpful when the database is being used for OLAP (Online Analytical Processing) use cases at MGM Resorts, as joins can be expensive and slow.

• Scalability: Denormalization can be like a turbo boost for your database's scalability! By requiring less data to be read and processed when executing a query, denormalization can help your database handle a ton of queries without breaking a sweat.

• Simplification: One way to simplify the design of a database is by using denormalization to reduce the number of tables and relationships that need to be managed. This can make the database easier to understand and maintain.

Of course, don't over-do the database denormalization magic – too much redundancy can increase data storage costs, and get complicated to manage if there's frequent commands that need to be run.

SQL Question 8: Analyzing Click-Through-Rates at MGM Resorts

As a data analyst at MGM Resorts, you have access to a plethora of data generated from digital marketing campaigns. Your task is to analyze the click-through rates (CTRs) of these campaigns. The CTR is calculated by dividing the number of users who clicked an ad (and subsequently made a booking) by the total number of users who viewed the ad.

You have two tables - and . The tables have the following data:

Example Input:

Example Input:

Answer:

This query first joins the and tables on and . It then groups by and calculates the CTR by dividing the number of distinct bookings (numerator) by the number of distinct ads (denominator). The ensures that we count all ads, even those without a corresponding booking.

Please note that the date fields are not used in this query; they could be useful for more complex analyses (e.g., considering only bookings made within a certain time after viewing an ad). Also, this query considers each ad-viewing as a separate event; if you wanted to calculate CTRs on a per-user basis, you would need to adjust the query accordingly.

To practice a similar problem on DataLemur's free interactive coding environment, solve this SQL interview question asked by Facebook:

SQL Question 9: Calculate the Average Daily Revenue Per MGM Resort

As a Data Analyst at MGM Resorts, you have been tasked with analyzing the revenue data. You need to figure out the average daily revenue generated by each resort.

Use the tables and provided below:

Example Input:

Example Input:

Calculate the average daily revenue of each resort.

Answer:

This query generates the average daily revenue of each resort. The table is joined with the table through the . The clause groups the rows by . The function is then used to compute the average daily revenue for each group.

SQL Question 10: What are the similarities and differences between correlated and non-correlated sub-queries?

While a correlated subquery relies on columns in the main query's clause and cannot function independently, a non-correlated subquery operates as a standalone query and its results are integrated into the main query.

An example correlated sub-query:

This correlated subquery retrieves the names and salaries of MGM Resorts employees who make more than the average salary for their department. The subquery references the column in the main query's clause () and uses it to filter the rows of the subquery's clause ().

An example non-correlated sub-query:

This non-correlated subquery retrieves the names and salaries of MGM Resorts employees who make more than the average salary for the Data Science department (which honestly should be very few people since Data Scientists are awesome and deserve to be paid well).The subquery is considered independent of the main query can stand alone. Its output (the average salary for the Data Science department) is then used in the main query to filter the rows of the MGM Resorts employees table.

SQL Question 11: Filter Customer Records at MGM Resorts

You have been given a database of customer records at MGM Resorts. Your task is to find all customers whose first name begins with 'J' and the email address contains 'gmail'.

Consider the following example input:

Example Input:

Example Output:

Answer:

You can write a SQL query in PostgreSQL as shown below:

This query uses the operator in the clause to filter out customers whose first name starts with 'J' and the email address contains 'gmail'. In the 'J%' pattern, '%' is a wildcard that matches zero or more characters, thus covering all first names that start with 'J'. Similar logic applies to the email pattern.

Preparing For The MGM Resorts SQL Interview

The key to acing a MGM Resorts SQL interview is to practice, practice, and then practice some more! Beyond just solving the above MGM Resorts SQL interview questions, you should also solve the 200+ DataLemur SQL Interview Questions which come from companies like Netflix, Airbnb, and Amazon.

Each interview question has multiple hints, full answers and most importantly, there's an online SQL coding environment so you can right online code up your SQL query and have it graded.

To prep for the MGM Resorts SQL interview you can also be a great idea to practice SQL questions from other hospitality and restaurant companies like:

• Yum Brands SQL questions
• Caesars Entertainment SQL questions
• Marriott SQL questions
• McDonald's SQL questions

However, if your SQL skills are weak, don't worry about diving straight into solving questions – refresh your SQL knowledge with this DataLemur SQL tutorial.

This tutorial covers SQL concepts such as filtering strings using LIKE and sorting results with ORDER BY – both of these show up frequently in SQL interviews at MGM Resorts.

MGM Resorts International Data Science Interview Tips

What Do MGM Resorts Data Science Interviews Cover?

Besides SQL interview questions, the other types of problems covered in the MGM Resorts Data Science Interview include:

• Probability & Statistics Questions
• Python Pandas or R Coding Questions
• Business Sense and Product-Sense Questions
• ML Interview Questions
• Behavioral & Resume-Based Questions

How To Prepare for MGM Resorts Data Science Interviews?

I believe the optimal way to study for MGM Resorts Data Science interviews is to read the book Ace the Data Science Interview.

It has 201 interview questions sourced from FAANG tech companies. The book's also got a refresher on Python, SQL & ML. And finally it's vouched for by the data community, which is why it's got over 1000+ 5-star reviews on Amazon.

While the book is more technical, it's also important to prepare for the MGM Resorts behavioral interview. A good place to start is by reading the company's unique cultural values.