Exercise 8.2 Answer the following questions about files and indexes: What operations are s...

Exercise 8.2 Answer the following questions about files and indexes:

1. What operations are supported by the file of records abstraction?
2. What is an index on a file of records? What is a search key for an index? Why do we need indexes?
3. What alternatives are available for the data entries in an index?
4. What is the difference between a primary index and a secondary index? What is a duplicate data entry in an index? Can a primary index contain duplicates?
5. What is the difference between a clustered index and an unclustered index? If an index contains data records as ‘data entries,’ can it be unclustered?
6. How many clustered indexes can you create on a file? Would you always create at least one clustered index for a file?
7. Consider Alternatives (1), (2) and (3) for ‘data entries’ in an index, as discussed in Section XXX. Are all of them suitable for secondary indexes? Explain.