POC Cheat Sheet 2026

The 30 highest-yield POC facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. How do you add an item to a list in Python? → list.append(item)
2. Which HTTP method is used to retrieve data from a server without modifying state? → GET
3. Which module is commonly used for debugging in Python? → pdb
4. What role does documentation play in system architecture? → It enables team understanding, maintenance, and future development decisions
5. What is the 80/20 rule as applied to performance optimization? → 80% of performance gains come from optimizing 20% of the code or configuration
6. What does the traceback module provide? → Error traceback information
7. In Python's `requests` library, how do you pass query string parameters in a GET request? → Using the `params` keyword argument with a dictionary
8. What decorator is used in unittest to mark a test that should be skipped? → @unittest.skip
9. What is the purpose of verifying a fix after implementation? → To confirm the solution resolved the issue without creating new problems
10. How do you check for syntax errors in Python? → Using a linter or running the code
11. Why is data validation important during integration? → It ensures data accuracy and consistency across connected systems
12. What HTTP status code indicates a successful request? → 200
13. Which Python tool is the standard for measuring code coverage during testing? → coverage.py
14. What is a deadlock in a multithreaded Python program? → A situation where two or more threads wait indefinitely for locks held by each other
15. What is the first step in a systematic troubleshooting approach? → Identify and clearly define the problem symptoms
16. What is the primary goal of data management? → Ensuring data quality, availability, and security throughout its lifecycle
17. What is the purpose of data lineage tracking? → To trace data origin, transformations, and movement through systems
18. What is the primary purpose of security auditing? → To identify vulnerabilities and verify compliance with security policies
19. What is the primary consideration when designing system architecture? → Scalability, reliability, and alignment with business requirements
20. In pytest, what built-in fixture provides a temporary directory for test files? → tmp_path
21. What is the principle of least privilege? → Granting users only the minimum access necessary to perform their duties
22. What is mocking in Python unit testing? → Replacing real objects with simulated ones to isolate units under test
23. Which of the following is used to handle exceptions? → try-except
24. What is the purpose of the __init__ method? → To initialize the object
25. Which method is used to read the entire content of a file? → read()
26. Which function can display the attributes of a module? → dir()
27. What is the primary benefit of automating repetitive tasks? → Reduced human error and increased consistency of results
28. Which data structure uses key-value pairs? → Dictionary
29. What is the correct way to create a variable in Python? → x = 10
30. What is capacity planning? → Predicting future resource needs based on growth trends and requirements