Mirabel Technologies interview questions

1. What is the use of COALESCE in SQl? 2. What are the Http Verbs ? 3. How to use HTTp Post? 4. WHat is query parameter ? 5. Explain Joins in Mssql? 6. WHat is trigger in SQL? 7. Define IsNull ? 8. How to send data from client to database ? 9. Find the second highest age in the given table Customers? https://www.programiz.com/sql/online-compiler/ 9.1. Find first_name, last_name from given table who bought 'Keyboard'? 10.What is difference in Abstract and Interface ?