Summary
The current chapter covered the fundamentals of indexing. The chapter built on the fundamentals of linear indexing, and extended it to ISAM. The linear indexing method is a good approach for static datasets which do not change over time; however, if any updates are required, they come at a very high computation cost. To address this issue, the ISAM indexing approach has been introduced, which tries to address the updating issue of databases. But it is still suitable for a few updates only.
The chapter also covered tree-based indexing structures which utilize the binary search tree-based structure to minimize search and updates. Multiple tree-based indexing approaches were also covered. The most primitive version is a 2-3 tree which uses the two-key and three-child strategy. The 2-3 tree indexing approach is a good starting point for tree-based indexing approaches, but retrieval of data from disk-based storage is slow.
The approach is further generalized as a B-tree which ensures that...