sql interview questions (sql queries)
1. Employees earning more than employee 103 2. Employees with the same job as employee 169 3. Employees earning the minimum salary of any department 4. Employees earning above the company’s average salary 5. Employees who report directly to Payam 6. All employees working in the Finance department 7. Employee whose salary is 3000 and manager ID is 121 8. Employees with IDs 134, 159, or 183 9. Employees earning between 1000 and 3000 10. Employees earning between the lowest salary and 2500 11. Employees not working in departments whose managers’ IDs are 100–200 12. Employees earning the second-highest salary
Read more100 SQL Commands — Simple & Unique Explanations
1–10: Basic Data & Structure Commands 11–20: Joins & Grouping 21–28: Sorting & Basic Functions 29–41: Conditions & Logical Tools 42–55: Keys, Constraints & Table Rules 56–77: Query Enhancers, Pagination & Date Functions 78–100: Advanced Aggregation, String Functions & Misc Section Title 100 SQL Commands — Simple & Unique Explanations ByMou December 5, 2025 Interview Preparation 1–10: Basic Data & Structure Commands 11–20: Joins & Grouping 21–28: Sorting & Basic Functions 29–41: Conditions & Logical Tools 42–55: Keys, Constraints & Table Rules 56–77: Query… Read More SQL Interview Questions & Answers (Advanced – 76 to 100) ByMou December 4, 2025
Read moreSQL Interview Questions & Answers (Advanced – 76 to 100)
76. What is Query Optimization? Query optimization means improving SQL performance so it runs faster. Ways to optimize: Example: 77. What is EXPLAIN in MySQL? EXPLAIN shows how MySQL will run a query.It helps find slow parts. 78. What is Sharding in Databases? Sharding means splitting a large database into smaller pieces (horizontal partition). Example: 79. What is Replication in MySQL? Replication copies data from Master to Slave servers for backup and load sharing. 80. Difference between Master and Slave in MySQL Replication? Master Slave Writes data Reads data Sends updates Receives updates Main DB Backup/Read DB 81. What is
Read moreSQL Interview Questions & Answers (Advanced Level – 51 to 75)
51. What is the ACID Property in SQL? ACID ensures reliable transactions. Property Meaning A – Atomicity All steps succeed or all fail. C – Consistency Data must remain valid before & after transaction. I – Isolation One transaction does not disturb another. D – Durability Changes survive even system crash. 52. What is a Transaction in SQL? A transaction is a group of SQL operations executed as a single unit. Example: 53. Difference between COMMIT and ROLLBACK? COMMIT ROLLBACK Saves changes permanently Undo all uncommitted changes Cannot revert Can revert until commit 54. What is Savepoint in SQL? A
Read moreSQL Interview Questions & Answers (Intermediate Level – 26 to 50)
26. What is a Subquery? A subquery is a query inside another query.It is used when you need the result of one query to use in another. Example: Get employees who earn more than the average salary: 27. What is a Nested Query? A nested query is another name for a subquery.It simply means a query inside another query. 28. What is a Correlated Subquery? A correlated subquery runs again and again, once for each row of the outer query. Example: Find employees whose salary is above their department average: 29. What is Group By in SQL? GROUP BY groups
Read moreSQL Interview Questions & Answers (Beginner Level – 1 to 25)
1. What is SQL? SQL (Structured Query Language) is a language used to store, manage, and retrieve data from a database. Example: This gets all records from the employees table. 2. What is a Database? A database is a place where data is stored in an organized way so it can be easily accessed. Example:MySQL database is like a folder that holds tables. 3. What are the types of SQL commands? 4. What is Primary Key? A Primary Key uniquely identifies each row in a table. Example: 5. What is Foreign Key? A Foreign Key links two tables together.It refers
Read moreService Portal Interview Questions & Answers (Simple + Unique + Examples)
Welcome to the ultimate guide on Service Portal Interview Questions & Answers. ⭐ SECTION 1: BASICS (FOR FRESHERS) 1. What is Service Portal in ServiceNow? Answer:Service Portal is a user-friendly website inside ServiceNow where employees can submit requests, search knowledge articles, raise incidents, etc. Example:When you open a company website to raise an IT ticket — that is a Service Portal page. 2. Why do companies use Service Portal in Service Portal Interview Questions & Answers? Answer:Because it provides:✔ Simple UI for non-technical users✔ Mobile-friendly experience✔ Easy to customize✔ Faster access to forms, catalog items, and knowledge 3. What is
Read moreITOM Interview Questions & Answers (Simple + Unique + With Examples)
⭐ Section 1: ITOM Basics (For Freshers) ⭐ ITOM Interview Questions & Answers 1. What is ITOM in ServiceNow? Answer:ITOM means managing all IT operations of an organisation — servers, applications, network devices, cloud, alerts, failures, etc.ServiceNow ITOM helps companies see everything running in IT, track changes, and prevent issues before they happen. Example:Imagine you’re running a hotel. ITOM is like a system that shows: 2. Why is ITOM used? Answer:Because companies want:✔ Zero downtime✔ Better visibility✔ Automatic discovery✔ Quick root-cause analysis✔ Reduced manual work 3. What are the main components of ITOM? Answer:ITOM in ServiceNow mainly includes: 4. What
Read moreITSM Interview Questions & Answers – Full Guide (Part 1 + Part 2 + Part 3)
ITSM Interview Questions & Answers – Full Guide (Part 1 + Part 2 + Part 3) PART 1 – BASIC ITSM QUESTIONS ======================================== What is ITSM? ITSM means IT Service Management. It manages IT services in a structured way. What is an Incident? An unplanned interruption to a service. Example: Wi-Fi down. What is a Problem? Root cause behind one or more incidents. Incident vs Problem? Incident = fix quickly. Problem = find root cause. What
Read moreEnglish Learning Course – Parts 46 to 50
🧠 English Learning Course – Parts 46 to 50 🌟 Part 46: Advanced Vocabulary for Fluent English As you move from intermediate to advanced English, your vocabulary must grow in depth (word power) and context (how to use words naturally). 💡 1. Learn Through Word Families A word family is a group of related words that share the same root. Root Word Noun Verb Adjective Adverb Beauty Beauty Beautify Beautiful Beautifully Success Success Succeed Successful Successfully Create Creation Create Creative Creatively Decide Decision Decide Decisive Decisively 📝 Tip: Try to learn one family of words per day, not just one
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