9 Clorox SQL Interview Questions (Updated 2024)

Clorox employees uses SQL to analyze sales trends across different product lines by tracking the performance of new product launches and identifying top-selling products. It is also used to manage customer data for targeted marketing campaigns by segmenting customers based on demographics and purchase history, which is why Clorox includes SQL questions during interviews for Data Science, Analytics, and & Data Engineering jobs.

So, to help you study, we've curated 9 Clorox SQL interview questions – can you answer each one?

9 Clorox SQL Interview Questions

SQL Question 1: Identify Top Purchasing Customers for Clorox

Clorox, a leading manufacturer and marketer of consumer and professional products, wants to identify their top customers who consistently make high-value purchases. This task is crucial for understanding and maintaining relationships with these "whale" or VIP customers.

Assume Clorox has a database with two tables: and . The table has columns , , , and . The table has columns , , , , and .

Sample Input:

Sample Input:

You are tasked with writing a SQL query to find the customers who have spent more than $2000 in total.

Answer:

This query joins the and tables on , aggregates the total order amount for each customer, and filters for customers who have spent more than $2000 in total. The result includes the names and emails of such customers, allowing for further contact or analysis.

To practice a related super-user data analysis question on DataLemur's free interactive coding environment, try this recently asked Microsoft SQL interview question:

SQL Question 2: 2nd Highest Salary

Assume there was a table of Clorox employee salary data. Write a SQL query to find the 2nd highest salary among all employees.

Clorox Example Input:

Example Output:

You can solve this problem directly within the browser on DataLemur:

Answer:

You can find a step-by-step solution with hints here: 2nd Highest Salary.

SQL Question 3: What's a primary key?

A primary key is a column or group of columns that uniquely identifies a row in a table. For example, say you had a database of Clorox marketing campaigns data:

In this Clorox example, the CampaignID column is the primary key of the MarketingCampaigns table. The constraint ensures that no two rows have the same CampaignID. This helps to maintain the integrity of the data in the table by preventing duplicate rows.

SQL Question 4: Analyze Monthly Average Ratings for Clorox Products

As a business analyst at Clorox, you have been tasked with analyzing product reviews data. Your specific task is to write a SQL query that will calculate the monthly average rating (stars) for each product.

Here's the table you will work with:

Example Input:

Based on the above dataset, you're expected to return a result that includes:

1. The year and month of review submission.
2. The product_id.
3. The average rating received that month for the product.

The expected output should look something like this:

Example Output:

Answer:

The above query makes use of PostgreSQL's window functions to group the data by year/month (using to convert the submission date to a year/month format) and product id in order to calculate the monthly average rating. The function calculates the average of the column for each product within each specific month. Finally, the result is sorted by and in ascending order.

Pro Tip: Window functions are a frequent SQL interview topic, so practice all the window function problems on DataLemur

SQL Question 5: Can you explain the purpose of the constraint?

A is a column or set of columns in a table that references the primary key of another table. It is used to link the two tables together, and to ensure that the data in the foreign key column is valid.

The constraint helps to ensure the integrity of the data in the database by preventing the insertion of rows in the foreign key table that do not have corresponding entries in the primary key table. It also helps to enforce the relationship between the two tables, and can be used to ensure that data is not deleted from the primary key table if there are still references to it in the foreign key table.

For example, if you have a table of Clorox customers and an orders table, the customer_id column in the orders table could be a that references the id column (which is the primary key) in the Clorox customers table.

SQL Question 6: Analyze Sales Performance for Clorox Products

Clorox sells a variety of products, from cleaning supplies to personal care items. They would like to analyze their sales across different regions to identify top performing products and potential areas for improvement.

You have been given two tables: and .

The table has the following structure:

• : Unique identifier for each sale.
• : The id of the product that was sold, which links to the in the table.
• : The geographical area where the product was sold.
• : The number of units sold in the sale.

The table has the following structure:

• : Unique identifier for each product.
• : Name of the product.
• : The category to which the product belongs.

Based on the data in these two tables, write a SQL query to find out the top 3 best selling products (in terms of units sold) for each region.

Example Input:

Example Input:

Answer:

Here's the SQL query in PostgreSQL:

With the given data, this script calculates the total units sold for each product in each region. It then assigns a row number for each product within each region, sorted by the total units sold in descending order (the line). The script then only selects the top 3 products for each region, as defined by the condition.

With the example data, this script would return the top three best selling products for each region, informing Clorox which products are performing best in terms of units sold in each region. This would help Clorox identify successful products and regions where sales could possibly be improved.

SQL Question 7: When it comes to database normalization, what's the difference between 1NF, 2NF, and 3NF?

Normal forms are guidelines that are used to help design a relational database in a way that minimizes redundancy and ensures the integrity of the data. The 3 most commonly use normal forms are the 1st, 2nd, and 3rd normal forms. Here's a brief explanation of each:

• 1st Normal Form (1NF) is all about keeping it simple - each column should only have one value and there should be no repeating groups of data.

• 2nd Normal Form (2NF) is about organization - your database should already be in 1NF and all the non-key columns should depend on the primary key. This means that each non-key column should be completely dependent on the entire primary key, not just part of it.

• 3rd Normal Form (3NF) is about independence - if your database is already in 2NF, then all the non-key columns should not depend on each other. They should be self-sufficient and not rely on other non-key columns.

SQL Question 8: Calculate the Average Quantity Sold per Product

At Clorox, you are given a sales transaction table that contains a record for each transaction detailing the product sold, the quantity of product sold and the date of sale. Can you write a SQL query to find out the average quantity sold per product for each year?

Example Input:

Example Output:

Answer:

This query first extracts the year from the sale_date and groups by it along with the product. The AVG function is then used to calculate the average quantity sold of each product for each year. The use of GROUP BY ensures that the average calculations are done for each product separately in each year, thereby giving us the desired output. The results are then ordered by year and product for better readability.

To practice a very similar question try this interactive Wayfair Y-on-Y Growth Rate Question which is similar for calculating year-on-year metrics or this Amazon Average Review Ratings Question which is similar for computing average quantities.

SQL Question 9: Average Sales Quantity per Product Category

As an analyst for Clorox, you are tasked with understanding the average sales quantity for each product category on a monthly basis. You have access to the and tables. The table records every sale including the product id and quantity sold. The table contains information about each product such as price, category and product id.

Please write a query that calculates the average quantity sold per category for each month.

Example Input:

Example Input:

Example Output:

Answer:

This SQL query first joins the and tables on the , and then groups the results by month and product category. The function is then used to calculate the average sale quantity for each group. By ordering the results by month and category, the output is easier to interpret.

Clorox 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. Besides solving the above Clorox 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.

Each SQL question has multiple hints, fully explained answers along with a discussion board to see how others solved it and most importantly, there's an online SQL coding environment so you can instantly run your query and have it graded.

To prep for the Clorox SQL interview it is also a great idea to solve SQL problems from other consumer good companies like:

• Fortune Brands SQL questions
• Masco SQL questions
• Newell Brands SQL questions
• Mohawk Industries SQL questions

Explore how Clorox is harnessing the power of AI to drive growth and innovation in the industry!

However, if your SQL coding skills are weak, don't worry about diving straight into solving questions – strengthen your SQL foundations with this DataLemur SQL Tutorial.

This tutorial covers SQL concepts such as RANK() window functions and advantages of CTEs vs. subqueries – both of which come up routinely in Clorox SQL assessments.

Clorox Data Science Interview Tips

What Do Clorox Data Science Interviews Cover?

In addition to SQL query questions, the other types of questions to practice for the Clorox Data Science Interview are:

• Statistics and AB Testing Questions
• Python or R Coding Questions
• Data Case Study Questions
• ML Modelling Questions
• Behavioral Interview Questions based on Clorox culture and values

How To Prepare for Clorox Data Science Interviews?

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

• 201 interview questions sourced from tech companies like Google & Microsoft
• a refresher covering SQL, Product-Sense & ML
• over 1000+ reviews on Amazon & 4.5-star rating

Don't ignore the behavioral interview – prepare for that with this guide on behavioral interview questions.