Chapter 22, Problem 16E

Explanation of Solution

a)

Attribute that are candidate for partitioning:

• In parallel systems, the data gets partitioned over different disks. The partitions are performed based on the attribute present in the relation.
• Consider a relation with specified work load of SQL queries. The candidate attribute for the partitioning would be
• The one which has maximum queries that holds selection condition. The condition is then evaluated using a single processor rather than performing all of them...

Explanation of Solution

b)

Choose between the alternative:

• To choose between the alternative partitioning techniques the cost based approach would be the best approach.
• Generate various candidates partitioning choice for each candidate too.
• The cost of estimating all the queries including the updates in the given workload.
• Choose the candidate that will lead to least cost.
• The problem is that usually both the number of candidate attributes and queries can be too large...

Explanation of Solution

c)

Partitioning a relation:

Yes, it is possible to partition a relation on more than one attribute in the following ways;

• Involving the attributes in a single compound partitioning key...