Problem:

Question 1- Describe how a direct search works using a B+-tree index

Question 2- Answer the following general questions about indexes:

Part 1- Can an index be built over a non-unique field?

Part 2- Can an index be built over a field if the file is not stored in sequence by that field?

Part 3- Can an index be built over a combination of fields as well as over a single field?

Part 4- Is there a limit to the number of indexes that can be built for a file?

Part 5- How is an index affected when a change is made to a file? Does every change to a file affect every one of its indexes?

Part 6- Can an index be used to achieve sequential access? Explain.

Could someone help to explain the answer of these questions.