1. B-tree indices are similar to B+-tree indices.
- Difference is that B-tree eliminates the redundant storage of search key values.
- In B+-tree of Figure 11.11, some search key values appear twice.
- A corresponding B-tree of Figure 11.18 allows search key values to appear only once.
- Thus we can store the index in less space.
2. Advantages:
- Lack of redundant storage (but only marginally di erent).
- Some searches are faster (key may be in non-leaf node).
3. Disadvantages:
- Leaf and non-leaf nodes are of di erent size (complicates storage)
- Deletion may occur in a non-leaf node (more complicated).Generally, the structural simplicity of B+-tree is preferred.