How the non-dense index worksHow the non-dense index works.pdf
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The document explains how non-dense indexes function, contrasting them with dense indexes where every search key has a corresponding index record. In a non-dense or sparse index, there is one entry for each block or unique value, which optimizes space but may require sequential searching if the desired data isn't directly located. This method improves efficiency while reducing the number of index records stored.
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How the non-dense index worksHow the non-dense index works.pdf
- 1. How the non-dense index works? How the non-dense index works? Solution Dense Index: An index record appears for every search key value in file. This record contains search key value and a pointer to the actual record. This makes searching faster but requires more space to store index records itself. Index records contain search key value and a pointer to the actual record on the disk. A non-dense index has: One entry for each block One entry for each different value Sparse Index is non-dense index In sparse index, index records are not created for every search key. An index record here contains a search key and an actual pointer to the data on the disk. To search a record, we first proceed by index record and reach at the actual location of the data. If the data we are looking for is not where we directly reach by following the index, then the system starts sequential search until the desired data is found.