Uploaded November 2025 | Updated September 2026, 1 day ago
Are you falling into the "ML for everything" trap? π§ Senior Data Scientists know that engineering maturity means delivering simple, robust, and effective solutions, and that often means avoiding the complexity of Machine Learning. In the rush to adopt AI, many junior practitioners reach for a neural network when a simple SQL query would do the job better, faster, and cheaper.
This video is about reaching Data Science maturity. We break down the costly pitfalls of over-engineering and show you exactly when a deterministic, rules-based approach is the superior choice over a probabilistic ML model.
What You Will Learn:
π‘ 3 Concrete Examples of when you should NOT use Machine Learning
π‘ Why simple solutions like a SQL query or Redis Sorted Set beat complex ML pipelines for real-time trending features.
π‘ The crucial difference between a deterministic (perfectly auditable) system and a probabilistic (ML) system, and why it matters for sensitive areas like billing.
π‘ How to Bootstrap your system with a simple rules engine to deliver immediate value and collect the necessary data to justify ML later.
The 3-Step Decision Framework (ML or Not ML?)
π οΈ We introduce a rigorous, three-step framework for making the right choice:
π οΈ Establish the Non-ML Baseline: Start with the simplest heuristic or rule-based solution. If it solves 80% of the problem, do you really need a complex model?
π οΈ Assess the Cost of an Error: Is a false positive (like an overcharge) or a false negative catastrophic? High-stakes domains demand a deterministic system.
π οΈ Determine the Need for Interpretability: Do you need to explain the decision to a regulator, customer, or auditor? A simple if-then-else is truly interpretable; a neural network is a black box.
Senior-level data science isn't about complexity; it's about delivering business value efficiently. Learn to choose the simplest, most robust solution.
π Subscribe for more insights on moving from a junior to a senior mindset in data science!
___________________________________
π Resources to Level Up Your Data Science Career
π Join our channel for no-BS data science advice : bit.ly/2GsFxmA
π Playlist for more data science interview questions and answers: bit.ly/3jifw81
π Playlist for data science interview tips: bit.ly/2G5hNoJ
π Playlist for data science projects: bit.ly/StrataScratchProjectsYouTube
π Practice more real data science interview questions: platform.stratascratch.com/coding?code_type=2&page_size=100&utm_source=youtube&utm_medium=click&utm_campaign=YT+are+you+using+machine+learning
______________________________________________________________________
π Video Timeline:
0:00 - Intro
0:44 - The "Most Popular" List
1:21 - The Billing System
2:00 - The New Product Launch
2:35 - Decision Framework: To ML or Not to ML
3:56 - Conclusion
______________________________________________________________________
About StrataScratch:
StrataScratch (platform.stratascratch.com/coding?code_type=2&page_size=100&utm_source=youtube&utm_medium=click&utm_campaign=YT+are+you+using+machine+learning) is a platform that allows you to practice real data science interview questions. There are over 1000+ interview questions that cover coding (SQL and Python), statistics, probability, product sense, and business cases.
So, if you want more interview practice with real data science interview questions, visit platform.stratascratch.com/coding?code_type=2&page_size=100&utm_source=youtube&utm_medium=click&utm_campaign=YT+are+you+using+machine+learning. All questions are free and you can even execute SQL and Python code in the IDE. Still, if you want to check out the solutions from other users or from the StrataScratch team, you can use ss15 for a 15% discount on the premium plans.
______________________________________________________________________
π§ Contact Us: Got questions or feedback? Drop them in the comments or email us at team@stratascratch.com.
_____________________________________________________________________
#DataScience #MachineLearning #MLOps #SeniorDataScientist #DataEngineering #AIStrategy #DataScienceCareer #SQL #MLTips
Are you falling into the "ML for everything" trap? π§ Senior Data Scientists know that engineering maturity means delivering simple, robust, and effective solutions, and that often means avoiding the complexity of Machine Learning. In the rush to adopt AI, many junior practitioners reach for a neural network when a simple SQL query would do the job better, faster, and cheaper.
This video is about reaching Data Science maturity. We break down the costly pitfalls of over-engineering and show you exactly when a deterministic, rules-based approach is the superior choice over a probabilistic ML model.
What You Will Learn:
π‘ 3 Concrete Examples of when you should NOT use Machine Learning
π‘ Why simple solutions like a SQL query or Redis Sorted Set beat complex ML pipelines for real-time trending features.
π‘ The crucial difference between a deterministic (perfectly auditable) system and a probabilistic (ML) system, and why it matters for sensitive areas like billing.
π‘ How to Bootstrap your system with a simple rules engine to deliver immediate value and collect the necessary data to justify ML later.
The 3-Step Decision Framework (ML or Not ML?)
π οΈ We introduce a rigorous, three-step framework for making the right choice:
π οΈ Establish the Non-ML Baseline: Start with the simplest heuristic or rule-based solution. If it solves 80% of the problem, do you really need a complex model?
π οΈ Assess the Cost of an Error: Is a false positive (like an overcharge) or a false negative catastrophic? High-stakes domains demand a deterministic system.
π οΈ Determine the Need for Interpretability: Do you need to explain the decision to a regulator, customer, or auditor? A simple if-then-else is truly interpretable; a neural network is a black box.
Senior-level data science isn't about complexity; it's about delivering business value efficiently. Learn to choose the simplest, most robust solution.
π Subscribe for more insights on moving from a junior to a senior mindset in data science!
___________________________________
π Resources to Level Up Your Data Science Career
π Join our channel for no-BS data science advice : bit.ly/2GsFxmA
π Playlist for more data science interview questions and answers: bit.ly/3jifw81
π Playlist for data science interview tips: bit.ly/2G5hNoJ
π Playlist for data science projects: bit.ly/StrataScratchProjectsYouTube
π Practice more real data science interview questions: platform.stratascratch.com/coding?code_type=2&page_size=100&utm_source=youtube&utm_medium=click&utm_campaign=YT+are+you+using+machine+learning
______________________________________________________________________
π Video Timeline:
0:00 - Intro
0:44 - The "Most Popular" List
1:21 - The Billing System
2:00 - The New Product Launch
2:35 - Decision Framework: To ML or Not to ML
3:56 - Conclusion
______________________________________________________________________
About StrataScratch:
StrataScratch (platform.stratascratch.com/coding?code_type=2&page_size=100&utm_source=youtube&utm_medium=click&utm_campaign=YT+are+you+using+machine+learning) is a platform that allows you to practice real data science interview questions. There are over 1000+ interview questions that cover coding (SQL and Python), statistics, probability, product sense, and business cases.
So, if you want more interview practice with real data science interview questions, visit platform.stratascratch.com/coding?code_type=2&page_size=100&utm_source=youtube&utm_medium=click&utm_campaign=YT+are+you+using+machine+learning. All questions are free and you can even execute SQL and Python code in the IDE. Still, if you want to check out the solutions from other users or from the StrataScratch team, you can use ss15 for a 15% discount on the premium plans.
______________________________________________________________________
π§ Contact Us: Got questions or feedback? Drop them in the comments or email us at team@stratascratch.com.
_____________________________________________________________________
#DataScience #MachineLearning #MLOps #SeniorDataScientist #DataEngineering #AIStrategy #DataScienceCareer #SQL #MLTips



![Data Science SQL Interview Question Walkthrough [Microsoft] - Window Function: Ranking
This Data Science SQL interview question is from Microsoft, and tests your ability to write window functions to rank data. Iβll walk you through solving the question like weβre in an interview and give you some tips on how to approach the solution.
Go to the question through the link below and follow along with me.
Link to the question: https://platform.stratascratch.com/coding/2026-bottom-2-companies-by-mobile-usage?python=&utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
π Subscribe to my channel: https://bit.ly/2GsFxmA
π Playlist for more data science interview questions and answers: https://bit.ly/3jifw81
π Playlist for data science interview tips: https://bit.ly/2G5hNoJ
π Practice more real data science interview questions: https://platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
Timeline:
Intro: (0:00βββ)
Interview Question: (0:31ββ)
Framework to solve the problem: (1:25βββ)
Understand your data: (2:33βββ)
Formulate your approach: (5:05βββ)
Code Execution: (7:09βββ)
Code Optimization: (15:54βββ)
Conclusion: (18:10βββ)
About The Platform:
Im using StrataScratch (https://platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link), a platform that allows you to practice real data science interview questions. There are over 1000+ interview questions that cover coding (SQL and python), statistics, probability, product sense, and business cases.
So, if you want more interview practice with real data science interview questions, visit https://platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link. All questions are free and you can even execute SQL and python code in the IDE, but if you want to check out the solutions from me or from other users, you can use ss15 for a 15% discount on the premium plans.
Contact:
If you have any questions, comments, or feedback, please leave them here!
Feel free to also email me at nathan@stratascratch.com
#MicrosoftDataScienceInterview Data Science SQL Interview Question Walkthrough [Microsoft] - Window Function: Ranking](https://i.ytimg.com/vi/i-E4pdU2qXM/mqdefault.jpg)





![Top Data Science Interview Question And Answer Mistakes 2021 [Asked By Amazon]
Were going to cover the #1 most common mistake made on data science interviews. This mistake is made by both inexperienced and experience data science professionals; it happens both on interviews and in the work setting; and the mistake takes place when trying to solve the most common data science question. Lets cover it so that you dont make the same mistake.
Follow me interactively with the question here: https://platform.stratascratch.com/coding/9915-highest-cost-orders?python=&utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
Platforms I recommend to practice data science real scenarios:
- https://platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link (data science questions)
- https://leetcode.com (general database questions)
- https://datacamp.com (niche specific analytical skillsets)
π Subscribe to my channel: https://bit.ly/2GsFxmA
π Playlist for more data science interview questions and answers: https://bit.ly/3jifw81
π Playlist for data science interview tips: https://bit.ly/2G5hNoJ
π Practice more real data science interview questions: https://platform.stratascratch.com/coding?utm_source=youtube&utm_medium=click&utm_campaign=YT+description+link
Timestamps:
Intro: (0:00)
Description of the most common mistake: (0:34)
Coding example of mistake: (1:00)
How to properly solve the question: (4:50)
Reason why youre making these mistakes: (7:30)
Recommendations to improve: (8:10)
Contact:
If you have any questions, comments, or feedback, please leave them here!
Feel free to also email me at nathan@stratascratch.com
#datascience #sqlinterviews #codinginterviews Top Data Science Interview Question And Answer Mistakes 2021 [Asked By Amazon]](https://i.ytimg.com/vi/j8kGqAAIhxA/mqdefault.jpg)
