- The homework submission date/time is 2022-MAY-01 at 11:59 PM.
- Submission format is a PDF version of this document with your answers. Place your answers in the document after the questions.
- The name of your PDF must be <UNI>_S22_W4111_HW4a_Written.pdf. For example, mine would be dff9_S22_W4111_HW3a_Written.pdf
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- Questions typically require less than five sentences for an answer. You will lose points if your answer runs on and wanders.
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Question 1: Explain why a sparse index must also be a clustering index.
Question 2: Briefly explain sparse, multi-level indexes and their benefits. Why can the outer index be sparse?
Question 3: Indexes can significantly improve performance? What are some disadvantages of having many indexes?
Question 4: Briefly compare the pros and cons of B+-Tree versus a Hash Index.
Question 5: Briefly explain the concepts of covering index/covered query.
Question 6: Briefly explain the three main steps/stages in query processing.
Question 8: Explain the role of equivalent queries in query optimization.
Question 9: Assume that the ON clause in a JOIN on tables A and B compares columns a1 with b1 and column a2 with b2. What two properties must the ON condition have for the optimizer to be able to use a Hash Join?