8 Ingredion SQL Interview Questions (Updated 2024)
Ingredion employees write SQL queries to analyze raw material supply data, helping them streamline procurement processes and ensure they have the right materials available when needed. They also use SQL to predict product quality trends by analyzing past production data, allowing them to address quality issues before they arise, this is the reason why Ingredion asks SQL problems in interviews for Data Science, Data Engineering, and Data Analytics jobs.
So, to help you prep, we've curated 8 Ingredion SQL interview questions – can you answer each one?
8 Ingredion SQL Interview Questions
SQL Question 1: Average Ingredient Purchase per Customer
Ingredion Incorporated is a global ingredients solutions company making various forms of starch, sweeteners, and nutritional ingredients for the food, beverage, brewing, and pharmaceutical sectors. Suppose you are provided with the following sample data stored in a table . Each row represents an ingredient purchase made by a customer. You are asked to write a SQL query to calculate the running average cost of each ingredient per customer as well as their total spend over the year 2022.
Example Input:
| purchase_id | customer_id | purchase_date | ingredient_id | cost |
|---|---|---|---|---|
| 5151 | 201 | 01/15/2022 | 6265 | 200 |
| 1208 | 201 | 01/20/2022 | 6265 | 250 |
| 8592 | 201 | 06/25/2022 | 6265 | 225 |
| 7459 | 638 | 04/10/2022 | 5843 | 150 |
| 3691 | 638 | 07/18/2022 | 5843 | 175 |
| 6898 | 638 | 12/13/2022 | 5843 | 200 |
Answer:
In the query above, we first use a window function to compute the cumulative average cost of each ingredient per customer for all purchases in 2022. In the main SELECT statement, we calculate the total spend per customer for each ingredient and also display the running average cost using the previously computed result in the CTE. Each row in the output table thus represents the customer's running average cost and total spend for a particular ingredient over the year 2022.
For more window function practice, try this Uber SQL problem on DataLemur's interactive SQL code editor:
Explore Ingredion's news events to stay informed about their latest innovations and contributions to the food and beverage industry! Understanding Ingredion's advancements can provide insights into how ingredient suppliers are shaping the future of food production.
SQL Question 2: Highly-Paid Employees
Given a table of Ingredion employee salary information, write a SQL query to find all employees who make more than their direct boss.
Ingredion Example Input:
| employee_id | name | salary | department_id | manager_id |
|---|---|---|---|---|
| 1 | Emma Thompson | 3800 | 1 | |
| 2 | Daniel Rodriguez | 2230 | 1 | 10 |
| 3 | Olivia Smith | 8000 | 1 | 8 |
| 4 | Noah Johnson | 6800 | 2 | 8 |
| 5 | Sophia Martinez | 1750 | 1 | 10 |
| 8 | William Davis | 7000 | 2 | NULL |
| 10 | James Anderson | 4000 | 1 | NULL |
Example Output:
| employee_id | employee_name |
|---|---|
| 3 | Olivia Smith |
This is the output because Olivia Smith earns $8,000, surpassing her manager, William Davis who earns 7,800.
Code your solution to this interview question interactively on DataLemur:
Answer:
First, we perform a SELF-JOIN where we treat the first table () as the managers' table and the second table () as the employees' table. Then we use a clause to filter the results, ensuring we only get employees whose salaries are higher than their manager's salary.
If the solution above is confusing, you can find a step-by-step solution with hints here: Employee Salaries Higher Than Their Manager.
SQL Question 3: What is the difference between a primary key and a foreign key?
To better understand the difference between a primary key and a foreign key, let's use an example from Ingredion's marketing analytics database, which holds data on Google Ads campaigns:
:
| ad_id | campaign_id | keyword | click_count |
|---|---|---|---|
| 1 | 100 | Ingredion pricing | 10 |
| 2 | 100 | Ingredion reviews | 15 |
| 3 | 101 | Ingredion alternatives | 7 |
| 4 | 101 | buy Ingredion | 12 |
In this table, serves as the primary key. It uniquely identifies each ad and cannot be null.
is a foreign key that connects to the of the corresponding Google Ads campaign. This establishes a relationship between the ads and their campaigns, enabling easy querying to find which ads belong to a specific campaign or which campaigns a specific ad belongs to.
The table may also have multiple foreign keys that reference primary keys in other tables. For example, and foreign keys could be used to link each ad to its ad group and the Google Ads account that the campaigns belong to, respectively.
SQL Question 4: Finding the Most Frequently Purchased Ingredient Type
Ingredion, a global company, specializes in supplying food and beverage ingredients for a wide variety of dishes and drinks. Suppose you are a data analyst at this company, you have a task to identify what are the most frequently purchased ingredient types for each client so that the company can anticipate demand and optimize supply chain management.
Here are your two tables:
Example Input:
| client_id | client_name |
|---|---|
| 1001 | Starbucks |
| 1002 | Burger King |
| 1003 | KFC |
Example Input:
| purchase_id | client_id | ingredient_type | purchase_date |
|---|---|---|---|
| 5001 | 1001 | Coffee Beans | 01/01/2022 00:00:00 |
| 5002 | 1001 | Coffee Beans | 01/02/2022 00:00:00 |
| 5003 | 1002 | Burger Bun | 01/03/2022 00:00:00 |
| 5004 | 1003 | Chicken Fillet | 01/04/2022 00:00:00 |
| 5005 | 1003 | Chicken Fillet | 01/05/2022 00:00:00 |
| 5006 | 1003 | Chicken Fillet | 01/06/2022 00:00:00 |
From the input data above, write a PostgreSQL query that provides the client name and the most frequently purchased ingredient type.
Answer:
This query first groups the purchase table by client_id and ingredient_type, counting the number of each type of ingredient bought by each client. We then find the maximum count of ingredients by client_id. In the end, we join the two CTEs and the clients table, where the counts equal the maximum value, to get the most frequently purchased ingredient for each client.
SQL Question 5: Can you explain what / SQL commands do?
For a tangible example of in PostgreSQL, suppose you were doing an HR Analytics project for Ingredion, and had access to Ingredion's contractors and employees data. Assume that some employees were previously contractors, and vice versa, and thus would show up in both tables.
You could use operator to find all contractors who never were a employee using this query:
Note that is available in PostgreSQL and SQL Server, while is the equivalent operator which is available in MySQL and Oracle (but don't worry about knowing which RDBMS supports which exact commands since Ingredion interviewers aren't trying to trip you up on memorizing SQL syntax).
SQL Question 6: Calculate the Average Ingredient Quantity Used Per Product
At Ingredion, they specialize in turning grains, fruits, vegetables, and other plant materials into ingredients for the food, beverage, brewing, and pharmaceutical industries and numerous industrial sectors. For a particular product, they might ask you to calculate the average ingredient quantity used across all batches of a product.
Consider the following tables:
Example Input:
| batch_id | product_id | batch_date |
|---|---|---|
| 101 | 1 | 06/01/2022 |
| 102 | 1 | 06/15/2022 |
| 103 | 2 | 06/20/2022 |
| 104 | 2 | 07/01/2022 |
| 105 | 1 | 07/05/2022 |
Example Input:
| batch_id | ingredient_id | quantity |
|---|---|---|
| 101 | 1 | 5 |
| 101 | 2 | 8 |
| 102 | 1 | 7 |
| 102 | 2 | 9 |
| 103 | 1 | 4 |
| 103 | 2 | 6 |
| 104 | 1 | 3 |
| 104 | 2 | 6 |
| 105 | 1 | 5 |
| 105 | 2 | 8 |
You need to write an SQL query that calculates the average quantity of each ingredient used per product.
Answer:
This PostgreSQL query joins the product_batches and batch_ingredients tables on the batch_id column. It then groups the selected rows by product_id and ingredient_id, calculating the average quantity per group.
To practice a very similar question try this interactive Amazon Highest-Grossing Items Question which is similar for calculating highest grossing items or this CVS Health Pharmacy Analytics (Part 1) Question which is similar for finding top profitable items.
SQL Question 7: Are NULLs handled the same as zero's and blank spaces in SQL?
A NULL value represents a missing or unknown value. It is different from a zero or a blank space, which are actual values. It is important to handle NULL values properly in SQL because they can cause unexpected results if not treated correctly.
SQL Question 8: Determining Click-Through Rate for Ingredion
As Ingredion's data analyst, one of your tasks is to monitor the click-through rates for the company's digital ads on a monthly basis. This is to help ascertain the effectiveness of the marketing campaigns and determine which ad was the most successful in a particular month.
You have been provided with two tables, and . The table records every time a customer clicks on an ad. The table records every instance an ad is viewed by a potential customer. Calculate the click-through rate, defined as the total number of ad clicks divided by the total number of ad views for each ad, for the month of May.
Example Input:
| click_id | ad_id | click_date |
|---|---|---|
| 817 | 21 | 05/02/2022 00:00:00 |
| 582 | 56 | 05/15/2022 00:00:00 |
| 593 | 21 | 05/25/2022 00:00:00 |
| 471 | 56 | 05/25/2022 00:00:00 |
| 735 | 33 | 05/29/2022 00:00:00 |
Example Input:
| view_id | ad_id | view_date |
|---|---|---|
| 6713 | 21 | 05/01/2022 00:00:00 |
| 7802 | 56 | 05/10/2022 00:00:00 |
| 5293 | 21 | 05/15/2022 00:00:00 |
| 6352 | 56 | 05/20/2022 00:00:00 |
| 4517 | 33 | 05/25/2022 00:00:00 |
Answer:
This PostgreSQL query first calculates the total ad clicks and views for the month of May. It does this by using the DATE_PART function to isolate the months where the clicks and views occurred. These are then grouped by ad_id to give us the counts. These two subqueries are then merged to give us a table showing the ad_id, total clicks, total views, and the click-through rate. A COALESCE function is used to handle potential NULL values for clicks, whilst a CASE statement handles potential NULL values for views.
To practice another question about calculating rates, try this TikTok SQL Interview Question on DataLemur's online SQL code editor:
How To Prepare for the Ingredion SQL Interview
The key to acing a Ingredion SQL interview is to practice, practice, and then practice some more! Beyond just solving the earlier Ingredion SQL interview questions, you should also solve the 200+ tricky sql questions on DataLemur which come from companies like FAANG tech companies and tech startups.
Each exercise has hints to guide you, step-by-step solutions and most importantly, there is an online SQL code editor so you can instantly run your SQL query and have it executed.
To prep for the Ingredion SQL interview it is also useful to solve interview questions from other food and facilities companies like:
- J.M. Smucker SQL questions
- Campbell Soup SQL questions
- Constellation Brands SQL questions
- Hershey SQL questions
But if your SQL foundations are weak, forget about jumping right into solving questions – refresh your SQL knowledge with this free SQL for Data Analytics course.
This tutorial covers SQL topics like aggreage functions like MIN()/MAX() and filtering strings using LIKE – both of which come up frequently in Ingredion interviews.
Ingredion Data Science Interview Tips
What Do Ingredion Data Science Interviews Cover?
In addition to SQL query questions, the other question categories covered in the Ingredion Data Science Interview are:
- Probability & Statistics Questions
- Python Pandas or R Coding Questions
- Product Analytics Questions
- ML Modelling Questions
- Behavioral Questions focussed on Ingredion values & principles
How To Prepare for Ingredion Data Science Interviews?
To prepare for Ingredion Data Science interviews read the book Ace the Data Science Interview because it's got:
- 201 interview questions sourced from tech companies like Netflix, Google, & Airbnb
- a refresher on Python, SQL & ML
- over 1000+ reviews on Amazon & 4.5-star rating
Also focus on the behavioral interview – prepare for it using this behavioral interview question bank.