What is a B*-tree primarily used for?

A B*-tree is primarily used in computer science for efficient data access. It is a type of self-balancing search tree that maintains sorted data in a manner that allows for efficient insertion, deletion, and search operations.

Here are the steps to understand its usage:

1. Data Storage: B*-trees are used to store large amounts of data by databases and file systems. They allow for efficient retrieval of the data by keeping the tree balanced.

2. Database Indexing: B*-trees are commonly used in databases for indexing data. This allows for faster search and retrieval of data from the database.

3. Multi-Level Indexing: B*-trees are also used for multi-level indexing where the first level of the index is stored in memory and the rest on the disk. This reduces the number of disk accesses and improves performance.

4. Efficient Disk Access: B*-trees are designed to minimize disk I/O operations. This is achieved by keeping the height of the tree low and ensuring that a large portion of the tree can be cached in memory.

5. Insertion and Deletion: B*-trees allow for efficient insertion and deletion of data. When data is inserted or deleted, the tree is re-balanced to maintain its properties.

6. Range Queries: B*-trees are also efficient for range queries. They allow for efficient retrieval of all records between an upper and lower bound.

In summary, B*-trees are primarily used for efficient data access in applications such as databases and file systems.