Assume the table has no index. What is the maximum number of blocks necessary to process the SELECT with a table scan?
Question
Assume the table has no index. What is the maximum number of blocks necessary to process the SELECT with a table scan?
Solution
The maximum number of blocks necessary to process the SELECT with a table scan would be equal to the total number of blocks that the table occupies in the database. This is because, without an index, the database management system has no way of knowing where the required data is located within the table. Therefore, it must scan every block in the table to ensure it doesn't miss the required data. This is why indexes are important in databases, as they allow the database management system to locate the required data without having to scan the entire table.
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