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    Question

    What is a characteristic feature of a dense index in a database indexing system?

    A Each index entry corresponds to a distinct value in the indexed column, and every value in the data file is represented in the index. Correct Answer Incorrect Answer
    B Each index entry corresponds to a distinct value in the indexed column, but only a subset of values is represented in the index. Correct Answer Incorrect Answer
    C The index contains a single entry for each unique data value, regardless of the number of occurrences in the data file. Correct Answer Incorrect Answer
    D The index provides a way to organize data in a tree-like structure for efficient search operations. Correct Answer Incorrect Answer
    E The index includes pointers to multiple values in the data file, but does not provide a direct mapping to the data. Correct Answer Incorrect Answer

    Solution

    A dense index is a type of index where there is a one-to-one correspondence between index entries and actual data entries in the indexed column. In other words, for every key value in the data file, there is a corresponding entry in the index. Key characteristics of a dense index include: • Complete Coverage: Every value of the indexed field in the data file is represented in the index. This means that if a value appears multiple times in the data file, there will be an index entry for each occurrence. • Direct Access: Since each value in the data file has an associated index entry, it allows for direct access to the data records. This can make searches and retrievals very efficient because the index provides a quick way to locate any specific record.

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