Question

This question is related to Database Management

Please don't answer using Handwriting

Draw an example of the spatial index R-tree and Quad tree and write the difference between them

Answer 1

Spatial index R-tree

R-tree is a tree data structure which is used to store spatial data indexes and spatial data queries. It is also used
for indexing multi-dimensional information , virtual maps implementation , measuring geographical coordinates .Most of all modern spatial databases and game engines use the spatial index R tree data structure.

Quad tree

In this tree data structure every node has exactly 4 child node . The number of leaves in a quad tree is a power of 4. All the records are stored in leaf nodes . But every leaf node may or may not has information . In the real world implementation a quad tree can contain billion or trillion of leaf nodes. Below is a quad tree of depth 3 .

Differences between Spatial index R-tree and Quad tree are mentioned below.

Spatial index R-tree	Quad tree
1. In this tree data structure index creation and tuning is easy.	1.In quad tree the creation of tuning is complex as it depends on several parameters .
2. A spatial index R-tree can be created by following a different structure from B- tree.	2. It can be implemented on top of existing B-tree .
3. If there is a lot of update activities then the performance of this tree is impacted .	3. Performance of this tree will not be impacted at all although there is a lot of update activity .
4. Spatal index creation in R tree is slower than quad tree. But if if the application workload includes nearest neighbor queries, R-tree indexes are faster.	4. Spatal index creation in quad-trees is faster than R tree. But if the application workload includes nearest neighbor queries, quad tree indexes are slower than R - Tree.
5. In this tree data structure less storage space is required .	5. For quad tree more storage is required as compared to R tree.
6. Whole-Earth Model requires R-tree index to determine the Whole-Earth index .	6. Whole-Earth index can not be determined from quad tree .
7. For Nearest Neighbour queries this tree data structure is faster than quad tree .	7. If the query is windows query then quad tree is faster than spatial index R tree .