10 Voya SQL Interview Questions (Updated 2024)
Data Analytics, Data Science, and Data Engineering employees at Voya write SQL queries to analyze financial transactions, such as tracking investment portfolios and identifying trends, as well as managing customer databases, including updating customer information and tracking policy changes, utilizing its structured querying capability for complex, industry-specific data manipulation. That is why Voya asks prospective hires SQL interview questions.
So, to help you prep for the Voya SQL interview, we've curated 10 Voya Financial SQL interview questions in this blog.
10 Voya Financial SQL Interview Questions
SQL Question 1: Calculate the running monthly average of insurance premiums
Voya Financial is an American company whose business is to help Americans plan, invest and protect their savings. One of its segments is Retirement, which provides retirement products and services in the United States.
Assume the company has a table named , that records the monthly insurance premiums for each customer. The table has the following structure:
Example Input:
| customer_id | product_id | premium_date | premium |
|---|---|---|---|
| 1740 | 120 | 2022/01/01 | 200.00 |
| 2743 | 134 | 2022/01/01 | 150.00 |
| 9001 | 120 | 2022/02/02 | 210.00 |
| 4792 | 134 | 2022/02/02 | 155.00 |
| 1740 | 120 | 2022/02/01 | 205.00 |
| 9001 | 120 | 2022/03/01 | 230.00 |
| 2743 | 134 | 2022/03/01 | 180.00 |
| 1740 | 120 | 2022/03/01 | 240.00 |
The interview question is: Write a SQL query to calculate the running monthly average of insurance premiums for each product. Which means, for each row, it calculates the average insurance premium from the start of the data to the current row's month. Result should be sorted by and .
The expected query output:
Example Output:
| product_id | premium_date | average_premium |
|---|---|---|
| 120 | 2022/01/01 | 200.00 |
| 120 | 2022/02/01 | 205.00 |
| 120 | 2022/03/01 | 215.00 |
| 134 | 2022/01/01 | 150.00 |
| 134 | 2022/02/01 | 152.50 |
| 134 | 2022/03/01 | 161.66 |
Answer:
The query can make use of window functions to calculate the aggregate value:
This query works by partitioning data by and for each product, it sorts the available premiums in ascending order by date. It then calculates the average premium over all rows from the start of the data to the current row, resulting in a running average. The clause specifies that the average is computed between the first row of the partition and the current row.
p.s. Window functions show up super often during SQL interviews, so practice the 27+ window function questions on DataLemur
SQL Question 2: 2nd Highest Salary
Given a table of Voya employee salaries, write a SQL query to find the 2nd highest salary among all employees.
Voya Example Input:
| employee_id | salary |
|---|---|
| 1 | 2500 |
| 2 | 800 |
| 3 | 1000 |
| 4 | 1200 |
Example Output:
| second_highest_salary |
|---|
| 1200 |
You can solve this interview question directly within the browser on DataLemur:
Answer:
You can find a step-by-step solution here: 2nd Highest Salary.
SQL Question 3: What's a constraint in SQL, and do you have any examples?
SQL constraints are used to specify rules for the data in a table. They can be applied to single or multiple fields in a table when the table is created, or after the table has been created using the ALTER TABLE command.
For example, say you had a database that stores ad campaign data from Voya's Google Analytics account.
Here's what some constraints could look like:
SQL Question 4: Investment Portfolio Analysis
Voya Financial Inc. is a financial company that offers various investment plans. You are tasked to help analyze the investment portfolios of it's clients. Design a database that keeps track of client data, types of investment plans, investments made by each client in various plans, and the corresponding dates.
Example Input:
| client_id | client_name |
|---|---|
| 1 | John Doe |
| 2 | Jane Doe |
| 3 | Ricky Romero |
Example Input:
| plan_id | plan_name | avg_year_return |
|---|---|---|
| 1 | Plan A | 5% |
| 2 | Plan B | 7% |
Example Input:
| investment_id | client_id | plan_id | invested_amount | investment_date |
|---|---|---|---|---|
| 1 | 1 | 1 | 1000.00 | 2021-01-01 |
| 2 | 1 | 2 | 2000.00 | 2021-05-01 |
| 3 | 2 | 1 | 1000.00 | 2021-03-01 |
| 4 | 3 | 2 | 3000.00 | 2021-01-01 |
SQL Question: Write a PostgreSQL query to find out total investment made by each client till July 2021.
Answer:
This query joins the table with the table and filters out the investments made by each client till July 2021. Then it groups the data by , calculates the total investment made by each client, and finally orders them in descending order of .
SQL Question 5: Does a typically give the same results as a ?
No, in almost all cases, and for all practical purposes, and do NOT produce the same result.
While both are similar, in that they combine two tables, you can think of joins as increasing the width of the resulting table (you'll have more columns in the result set for a left/inner/right join), whereas a union is used to combine rows which increases the height of the result set but keeps the column count the same.
SQL Question 6: Filter Out Customers based on given conditions
Voya has a customer information database that contains various details about individual customers. For business analysis, Voya is interested in filtering out data that satisfies multiple conditions. Write a SQL query to filter out the customers who are older than 50 years and their account status is active or those who have lifetime deposits greater than $50000.
The customer records database is named CustomerInfo. The following columns are available in the CustomerInfo database:
- : The unique identifier for each customer
- : The age of the customer
- : Indicates if a customer's account is active or not
- : The total amount of money deposited by the customer over a lifetime.
Example Input
| customer_id | age | status | lifetime_deposit |
|---|---|---|---|
| 001 | 45 | active | $30,000 |
| 002 | 55 | active | $60,000 |
| 003 | 65 | inactive | $20,000 |
| 004 | 45 | inactive | $30,000 |
| 005 | 60 | inactive | $80,000 |
| 006 | 50 | active | $40,000 |
| 007 | 55 | inactive | $90,000 |
Answer:
Here is the PostgreSQL query to filter the required customers data:
This query applies multiple boolean conditions to filter out the data. It first looks for all rows where the . Then it filters out rows where the . The OR operator is used to combine these conditions, so a row will be selected if either of these conditions is met.
SQL Question 7: What's the purpose of the function in SQL?
The function can take in multiple paramaters, and returns the first input paramater that is not null. If all arguments are null, the COALESCE function will return null too.
Suppose you have a table of Voya salespeople and the number of deals they closed. If a salesperson didn't close any deals, the data from the 3rd-party CRM system exports a NULL value.
| sales_person | closed_deals |
|---|---|
| Jason Wright | NULL |
| Drew Jackson | 3 |
| Chris Ho | NULL |
| Adam Cohen | 2 |
| Samantha Perez | 4 |
To change these NULLs to zeros, you can use the function in the following way:
This would result in the following data:
| sales_person | closed_deals |
|---|---|
| Jason Wright | 0 |
| Drew Jackson | 3 |
| Chris Ho | 0 |
| Adam Cohen | 2 |
| Samantha Perez | 4 |
SQL Question 8: Calculate Average Investment Return Rate
As a Data Analyst at Voya, an American retirement, investment and insurance company, you have access to client's investment data. Your task is to write a SQL query that calculates average return rate for each investment type for the year 2022.
Sample data can be retrieved from table:
Example Input:
| investment_id | client_id | investment_type | purchase_date | total_investment | total_return |
|---|---|---|---|---|---|
| 2431 | 123 | Stocks | 02/03/2022 | 5000 | 5700 |
| 3521 | 354 | Bonds | 01/11/2022 | 10000 | 10500 |
| 1542 | 892 | Mutual Funds | 06/25/2022 | 8000 | 8640 |
| 2376 | 123 | Stocks | 12/08/2022 | 7000 | 7210 |
| 7896 | 354 | Bonds | 04/18/2022 | 12000 | 12960 |
You need to identify the average return rate for each investment type in 2022. Return rate can be calculated by ((total_return - total_investment) / total_investment).
Answer:
Here is a PostgreSQL query to solve this problem:
This SQL query first filters rows in the 'investments' table to get records purchased in 2022. It then groups the result by 'investment_type'. For each group, it calculates the average return rate using total_return and total_investment columns of the corresponding group. The result will be the average return rate for each investment type in 2022.
To practice a very similar question try this interactive Wayfair Y-on-Y Growth Rate Question which is similar for calculating year-on-year growth rate or this Amazon Average Review Ratings Question which is similar for computing average ratings per group.
SQL Question 9: Find Customers From a Specific City
As a customer service representative at Voya, you are tasked with identifying customers who are from New York City for a specialized marketing campaign. Your task is to write an SQL query that picks out customers from the table whose field contains the string 'New York City'.
Consider the following structure and data of the table:
Example Input:
| customer_id | first_name | last_name | address | |
|---|---|---|---|---|
| 315 | John | Doe | johndoe@gmail.com | 123 Broadway Avenue, New York City |
| 932 | Jane | Smith | janesmith@yahoo.com | 456 Main Street, Los Angeles |
| 491 | Mary | Johnson | maryjohnson@hotmail.com | 789 Park Avenue, New York City |
| 712 | James | Brown | jamesbrown@icloud.com | 321 Elm Street, Chicago |
| 253 | Patricia | Williams | patriciawilliams@gmail.com | 654 Pine Street, New York City |
Answer:
The SQL query to solve the problem would be as follows:
This SQL query will find and return all records in the 'Customers' table where the 'address' field contains the string 'New York City'. It uses the LIKE keyword in SQL, which allows you to search for a specified pattern in a column. The '%' sign used before and after 'New York City' allows any sequence of characters before and after the string.
The output will include all the columns for customers from New York City. Based on the given sample data, it would return the rows for customer_id values 315, 491, and 253.
SQL Question 10: How is a foreign key different from a primary key in a database?
A primary key is a column (or set of columns) in a table that uniquely identifies each row in the table. It cannot contain null values and must be unique across all rows in the table.
A foreign key is a column (or set of columns) in a table that references the primary key of another table. It is used to establish a relationship between the two tables. A foreign key can contain null values, and multiple rows in the referencing table can reference the same row in the referenced table.
For example, consider a database with two tables: and . The Voya customers table might have a primary key column called , while the Voya orders table might have a foreign key column called that references the column in the table. This establishes a relationship between the two tables, such that each row in the orders table corresponds to a specific Voya customer.
Voya SQL Interview Tips
The best way to prepare for a SQL interview, besides making sure you have strong SQL fundamentals, is to practice a ton of real SQL questions that were asked in recent job interviews. In addition to solving the above Voya SQL interview questions, you should also solve the 200+ DataLemur interview questions which come from companies like Google, Uber, and Microsoft.
Each interview question has hints to guide you, fully explained answers along with a discussion board to see how others solved it and best of all, there is an online SQL code editor so you can instantly run your query and have it graded.
To prep for the Voya SQL interview you can also be wise to solve SQL problems from other insurance companies like:
- Voya SQL questions
- Sentry Insurance SQL questions
- Digital Realty Trust SQL questions
- American National SQL questions
Discover how Voya Financial is harnessing the potential of machine learning to drive investment success!
However, if your SQL query skills are weak, don't worry about jumping right into solving questions – strengthen your SQL foundations with this SQL tutorial for Data Analytics.
This tutorial covers SQL concepts such as joining multiple tables and rank window functions – both of these come up frequently during SQL interviews at Voya.
Voya Financial Data Science Interview Tips
What Do Voya Data Science Interviews Cover?
Beyond writing SQL queries, the other types of questions covered in the Voya Data Science Interview include:
- Statistics and Probability Questions
- Python Pandas or R Coding Questions
- Product Analytics Questions
- Machine Learning Questions
- Behavioral Interview Questions centered on Voya culture and values
How To Prepare for Voya Data Science Interviews?
To prepare for Voya Data Science interviews read the book Ace the Data Science Interview because it's got:
- 201 interview questions sourced from FAANG, tech startups, and Wall Street
- a refresher on SQL, Product-Sense & ML
- over 1000+ 5-star reviews on Amazon
Also focus on the behavioral interview – prep for that with this guide on acing behavioral interviews.