Learn SQL in 7 days - (SDET)

Here's a condensed 7-day plan that covers all the essential SQL topics for QA, along with top 25 interview questions for an SDET (Software Development Engineer in Test) lead role.

7-Day Learning Plan for SQL for QA

Day 1. Introduction to SQL, Basic SQL Queries, Aggregate Functions
Day 2. SQL Joins, Advanced SQL Functions, Subqueries and Nested Queries
Day 3. Data Manipulation (INSERT, UPDATE, DELETE), Data Definition Language (DDL)
Day 4. Indexes and Performance Tuning, SQL Views and Stored Procedures
Day 5. Transactions and Concurrency Control, Error Handling and Exception Handling in SQL
Day 6. SQL Security and Permissions, Practical Case Study 1, Practical Case Study 2
Day 7. Review and Practice, Mock Interviews, Advanced Topics (NoSQL vs SQL, JSON, XML), Data Warehousing, ETL, Big Data

Detailed Explanation
Day 1: Introduction to SQL, Basic SQL Queries, Aggregate Functions
Topics:
Basic concepts of databases and SQL syntax
Installation of SQL tools (e.g., MySQL, PostgreSQL)
SELECT, FROM, WHERE
Aggregate functions: COUNT, SUM, AVG, MIN, MAX
Activities: Install SQL software, write basic queries, and practice aggregation.

Day 2: SQL Joins, Advanced SQL Functions, Subqueries and Nested Queries
Topics:
INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL JOIN
GROUP BY, HAVING, ORDER BY
Subqueries and nested queries
Activities: Write complex queries combining data from multiple tables, practice grouping, sorting, and filtering data.

Day 3: Data Manipulation (INSERT, UPDATE, DELETE), Data Definition Language (DDL)
Topics:
INSERT, UPDATE, DELETE statements
DDL commands: CREATE, ALTER, DROP
Activities: Modify database records, create and alter database structures.

Day 4: Indexes and Performance Tuning, SQL Views and Stored Procedures
Topics:
Creating indexes, performance tuning techniques
Creating and using views, writing stored procedures
Activities: Optimize queries, develop reusable SQL code with views and stored procedures.

Day 5: Transactions and Concurrency Control, Error Handling and Exception Handling in SQL
Topics:
ACID properties, handling transactions, managing concurrency
Error handling mechanisms, TRY...CATCH blocks
Activities: Implement transactions, handle concurrency issues, and error handling in SQL scripts.

Day 6: SQL Security and Permissions, Practical Case Study 1, Practical Case Study 2
Topics:
Managing user permissions, ensuring database security
Applying learned concepts to real-world projects
Activities: Grant and revoke permissions, and develop projects involving database design and query development.

Day 7: Review and Practice, Mock Interviews, Advanced Topics (NoSQL vs SQL, JSON, XML), Data Warehousing, ETL, Big Data
Topics: Review key concepts, mock interviews
NoSQL vs SQL, handling JSON and XML in SQL
Data warehousing concepts, ETL processes, SQL for big data
Activities: Comprehensive revision, practice interview questions, explore advanced topics, and big data handling.

Top 25 Interview Questions for SDET Lead Role

1. Explain the role of an SDET in an Agile team.
2. How do you ensure the quality of test automation scripts?
3. Describe your experience with continuous integration and continuous deployment (CI/CD) pipelines.
4. What strategies do you use to handle flaky tests?
5. Explain how you prioritize test cases in a limited time frame.
6. Describe a challenging bug you found and how you resolved it.
7. What is the importance of code reviews in test automation?
8. How do you measure the success of your test automation?
9. Explain the concept of test-driven development (TDD) and how you've applied it.
10. What tools and frameworks have you used for test automation?
11. How do you approach performance testing?
12. Describe your experience with API testing and tools used.
13. What is the difference between functional and non-functional testing?
14. How do you manage and maintain test data?
15. What is your experience with version control systems like Git?
16. How do you ensure security in your test automation scripts?
17. Describe a time when you had to mentor a junior SDET.
18. How do you handle changes in requirements during the testing phase?
19. Explain your approach to testing microservices.
20. What is your experience with mobile testing?
21. How do you integrate testing with DevOps practices?
22. Describe your approach to testing in a cloud environment.
23. What are the key components of a good test plan?
24. How do you stay updated with the latest testing tools and technologies?
25. Explain how you handle test environment setup and management.

This 7-day plan and the interview questions should help you gain a comprehensive understanding of SQL for QA and prepare for a lead role in SDET.