10 Archer Daniels Midland SQL Interview Questions (Updated 2024)

Updated on

October 31, 2024

At Archer Daniels Midland, SQL plays a big role in analyzing agricultural trends across different geographic regions, helping the company understand how various factors affect crop production and pricing. They also use SQL to predict grain market behavior based on past sales data, allowing them to make smart decisions about inventory and sales strategies, which is why Archer Daniels Midland often asks SQL query questions in interviews for Data Analyst, Data Science, and BI jobs.

Thus, to help you prepare for the Archer Daniels Midland SQL interview, here's 10 Archer Daniels Midland SQL interview questions – can you solve them?

Archer Daniels Midland SQL Interview Questions

10 Archer Daniels Midland SQL Interview Questions

SQL Question 1: Identify the top buying customers for Archer Daniels Midland

Archer Daniels Midland is a global food processing company. Assume you are given two tables, and . The table records all orders placed by customers, and table contains information about all Archer Daniels Midland customers. We define a power buyer as a customer who has made large total purchases. For simplicity, create a SQL query to identify the 10 customers who have made the highest total purchases in 2021.

Example Input:

order_idcustomer_idorder_dateorder_total
10112021-07-15500.00
10222021-02-20250.00
10312021-09-181500.00
10432021-04-12300.00
10522021-12-10400.00

Example Input:

customer_idcustomer_nameregion
1John DoeNorth
2Jane SmithSouth
3Adam BrownEast

SQL Query:


This SQL query first joins the table with the , and then filters to include only the rows where the year of the is 2021. It then groups the data by , and computes the sum of for each customer. Finally, it orders the result in descending order, and limits the output to the top 10 customers with the highest total purchases in 2021.

To work on a similar customer analytics SQL question where you can code right in the browser and have your SQL code instantly executed, try this Walmart Labs SQL Interview Question:

Walmart Labs SQL Interview Question

SQL Question 2: 2nd Largest Salary

Assume there was a table of Archer Daniels Midland employee salary data. Write a SQL query to find the 2nd highest salary at the company.

Archer Daniels Midland Example Input:

employee_idsalary
12500
2800
31000
41200

Example Output:

second_highest_salary
1200

Test your SQL query for this interview question and run your code right in the browser:

2nd Highest Salary SQL Interview Question

Answer:


You can find a detailed solution here: 2nd Highest Salary.

SQL Question 3: What's the difference between and clause?

The clause is used to filter the groups created by the clause. It's similar to the clause, but it is used to specify conditions on the groups created by the clause, rather than on the individual rows of the table.

For example, say you were analyzing salaries for analytics employees at Archer Daniels Midland:


This query retrieves the total salary for each Analytics department at Archer Daniels Midland and groups the rows by the specific department (i.e. "Marketing Analytics", "Business Analytics", "Sales Analytics" teams).

The clause then filters the groups to include only Archer Daniels Midland departments where the total salary is greater than $1 million

Archer Daniels Midland SQL Interview Questions

SQL Question 4: Calculate Average Monthly Price of each Commodity

Archer Daniels Midland is one of the largest commodity trading companies in the world. For this exercise, imagine you are working with a dataset that contains information on commodity prices for each transaction that happened. Your task is to write a SQL query to calculate the average monthly price for each commodity using window functions.

Here is the structure of data you are given:

Example Input:

transaction_idtransaction_datecommodityprice
101/02/2022corn5.3
202/14/2022corn6.2
302/28/2022soybean8.3
402/20/2022corn5.6
503/12/2022soybean7.9

We want to get a result like this:

Example Output:

year_monthcommodityavg_price
2022-02corn5.9
2022-02soybean8.3
2022-03soybean7.9

Answer:

Here is a PostgreSQL query that solves this problem:


This query uses to convert to 'Year-Month' format. The window function is used to calculate the average price for each commodity for each month. It uses to calculate the average separately for each month and each commodity. Then it sorts the result by and .

To solve another window function question on DataLemur's free online SQL coding environment, solve this Amazon BI Engineer interview question:

Amazon Window Function SQL Interview Problem

SQL Question 5: What is denormalization?

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

Denormalization is done to improve the performance of the database when it is being used for online analytics processing (OLAP), rather than online transaction processing (OLTP) use cases.

For these OLAP use cases, you're bottleneck frequently is joining multiple tables, but de-normalizing your database cuts these outs.

Denormalization can improve query performance by reducing the number of expensive joins required to retrieve data, but it comes with its own drawbacks too. By adding redundant columns, you incur more data storage costs, and there's need for more complex update and delete operations in order to maintain data integrity across all the duplicated data. Thus, it's important to carefully consider the trade-offs involved before implementing denormalization.

SQL Question 6: Average Quantity of Grain Produced

Archer Daniels Midland (ADM) is a global food processing and commodities trading corporation. One of their major products is grain.

Given a table with fields , , and , where is the quantity of grains produced in kilogram, can you write a SQL query to find the average quantity of grain produced in each quarter of the year 2022?

Example Input:

farm_idharvest_datequantity(kg)
10122022-01-153000
35002022-02-205000
10122022-02-284500
35002022-04-106000
10122022-07-157000
35002022-08-207500
10122022-11-288000
35002022-12-108500

Example Output:

quarteraverage_quantity(kg)
Q14166.67
Q26000.00
Q37250.00
Q48250.00

Answer:


This query groups the data in by quarter of the year 2022 and calculates the average quantity of grain produced in each quarter. The function is used to extract the month and year from , and the statement is used to classify the months into quarters. Finally, the function calculates the average quantity produced for each of the quarters, and the clause sorts the output by quarter.

To practice a very similar question try this interactive Facebook Active User Retention Question which is similar for querying specific date ranges or this Amazon Average Review Ratings Question which is similar for calculating averages grouped by time periods.

SQL Question 7: What does do in a SQL query?

In SQL, the operator combines the result of two or more SELECT statements into a single result set. Note that each statement within the must have the same number of columns and the columns must have similar data types. The operator removes duplicates from the final result set. If you want to include duplicates in the final result set, you can use the operator instead.

Here's an example of using the operator to combine the results of two statements that retrieve data from tables of Archer Daniels Midland's Facebook ads and their Google ads:


This statement would return a combined result set of both Facebook and Google ads that have a spend greater than $500.

SQL Question 8: Calculate the Click-Through-Rate (CTR) for Different Categories of Products

Archer Daniels Midland, a major food processing and commodities trading corporation, has an online platform they use to market their different categories of products. They want to calculate the Click-Through-Rate (CTR) for different categories of products based on impressions (number of times an ad is shown) and clicks (number of time the ad is clicked).

Example Input:

impression_idcategory_idimpression_dateuser_id
100130006/08/2022 00:00:00123
100220006/10/2022 00:00:00635
100310006/18/2022 00:00:00362
100420007/26/2022 00:00:00981
100530007/05/2022 00:00:00192

Example Input:

click_idcategory_idimpression_idclick_dateuser_id
2001300100106/08/2022 00:00:00123
2002200100206/11/2022 00:00:00635
2003100100306/18/2022 00:00:00362

Answer:


This query will return the Click-Through-Rate (CTR) for different categories of products. It first joins the two tables on the as it is common to both tables. Then it groups by the to calculate the metrics: number of impressions, number of clicks, and Click-Through-Rate (CTR), which is calculated by dividing total clicks by total impressions. A is used to ensure all ad impressions are included, even if they didn't receive any clicks.

To practice a similar problem about calculating rates, try this SQL interview question from TikTok on DataLemur's interactive coding environment:

TikTok SQL Interview Question

SQL Question 9: Calculate Average Sales

Archer Daniels Midland (ADM) is a company engaged in food processing and commodities trading. Let's say you are working with a database that contains all sales made by the company. The SQL question is to write a query that calculates the total sales and average sales price by product category for the year 2020.

Example Input:

sale_idsale_dateproduct_categoryprice
345601/03/2020Corn1200
342701/05/2020Soybeans1250
356202/03/2020Corn1280
378903/06/2020Wheat1050
383904/11/2020Corn1300

Example Output:

product_categorytotal_salesavg_sales_price
Corn31260
Soybeans11250
Wheat11050

Answer:

The query for this would look something like:


This SQL query calculates the total number of sales () and the average sale price () for each product category () in the year 2020.

SQL Question 10: When it comes to database normalization, what's the difference between 1NF, 2NF, and 3NF?

There are several normal forms that define the rules for normalizing a database:

A database is in first normal form (1NF) if it meets the following criteria:

  • Each column in a table contains a single value (no lists or containers of data)
  • Each column should contain the same type of data (no mixing strings vs. integers)
  • Each row in the table is unique

A database is in second normal form (2NF) if it meets the following criteria:

  • It is in first normal form.
  • All non-key attributes in a table are fully dependent on the primary key.

Said another way, to achieve 2NF, besides following all the rules from 1NF all the columns in a given table should be dependent only on that table's primary key.

A database is in third normal form (3NF) if it meets the following criteria:

  • It is in second normal form.
  • There are no transitive dependencies in the table.

A transitive dependency means that a piece of data in one column is derived from another column. For example, it wouldn't make sense to keep a column called "user's age" and "user's birthdate" (because age can be derived from birthdate.

While there's also a 4th and 5th normal form, it's too pedantic and hence out-of-scope to know for the Archer Daniels Midland SQL interview.

How To Prepare for the Archer Daniels Midland SQL Interview

Assuming that you've already got basic SQL skills, the next best tip we have to prepare for the Archer Daniels Midland SQL interview is to solve as many practice SQL interview questions as you can! In addition to solving the earlier Archer Daniels Midland SQL interview questions, you should also solve the 200+ FAANG SQL Questions on DataLemur which come from companies like Amazon, Microsoft, Meta, and smaller tech companies.

DataLemur SQL Interview Questions

Each exercise has hints to guide you, fully explained answers along with a discussion board to see how others solved it and best of all, there's an interactive coding environment so you can instantly run your SQL query and have it checked.

To prep for the Archer Daniels Midland SQL interview you can also be a great idea to practice SQL questions from other food and facilities companies like:

In case your SQL skills are weak, forget about going right into solving questions – go learn SQL with this SQL tutorial for Data Scientists & Analysts.

DataLemur SQL Tutorial for Data Science

This tutorial covers things like AND/OR/NOT and creating summary stats with GROUP BY – both of these show up often in Archer Daniels Midland SQL interviews.

Archer Daniels Midland Data Science Interview Tips

What Do Archer Daniels Midland Data Science Interviews Cover?

In addition to SQL interview questions, the other types of problems to prepare for the Archer Daniels Midland Data Science Interview are:

Archer Daniels Midland Data Scientist

How To Prepare for Archer Daniels Midland Data Science Interviews?

To prepare for Archer Daniels Midland Data Science interviews read the book Ace the Data Science Interview because it's got:

  • 201 interview questions taken from FAANG (FB, Apple, Amazon, Netflix, Google)
  • a refresher covering SQL, Product-Sense & ML
  • over 1000+ reviews on Amazon & 4.5-star rating

Acing Data Science Interview

Don't forget about the behavioral interview – prep for it using this Behavioral Interview Guide for Data Scientists.

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