1. Consider the three basic techniques, iteration, indering, and partitioning, and the relational algebra operators selection, projection, and join. For each technique- operator pair, describe an...

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Extracted text: 1. Consider the three basic techniques, iteration, indering, and partitioning, and the relational algebra operators selection, projection, and join. For each technique- operator pair, describe an algorithm based on the technique for evaluating the operator. 2. Define the term most selective access path for a query. 3. Describe conjunctive normal form, and explain why it is important in the context of relational query evaluation. 4. When does a general selection condition match an index? What is a primary term in a selection condition with respect to a given index? 5. How does hybrid hash join improve on the basic hash join algorithm? 6. Discuss the pros and cons of hash join, sort-merge join, and block nested loops join. 7. If the join condition is not equality, can you use sort-merge join? Can you use hash join? Can you use index nested loops join? Can you use block nested loops join? 8. Describe how to evaluate a grouping query with aggregation operator MAX using a sorting-based approach. 9. Suppose that you are building a DBMS and want to add a new aggregate operator called SECOND LARGEST, which is a variation of the MAX operator. Describe how you would implement it. 10. Give an example of how buffer replacement policies can affect the performance of a join algorithm.