Why coalesce is used in SQL?

Related questions

1. What is the difference between NVL and nvl2 functions in SQL?
2. What does NVL mean in SQL?
3. How do I use Isnull in SQL?
4. IS NULL function in PostgreSQL?
5. IS NOT NULL PostgreSQL?
6. What is coalesce in PostgreSQL?
7. How does coalesce work in SQL?
8. How do I write Isnull in SQL?
9. What is the difference between coalesce and NVL?
10. How do I rename a table in SQL?

Tags

1. #first
2. #isnull
3. #values
4. #replaced
5. #evaluation
6. #arguments
7. #handle
8. #function
9. #argument
10. #always
11. #process
12. #during
13. #evaluates
14. #functions
15. #coalesce
16. #expression
17. #order
18. #defined
19. #value
20. #returns