Can you explain the principle of operation of B-trees and where they are used?

A B-tree is a balanced search tree optimized for handling large volumes of data, often used in databases and file systems.

Core principles:

• Each node contains multiple keys and child pointers, reducing tree height.
• All leaves are at the same level, ensuring balance.
• Nodes can contain from t-1 to 2t-1 keys (where t is the minimum degree).
• During insertion and deletion, keys are redistributed, and nodes are split or merged to maintain balance.

Applications:

• Indexing in databases (e.g., MySQL, PostgreSQL).
• File systems for fast data search and insertion.
• Any system requiring high performance with large disk data volumes.

A usage example in Go can be implemented via structures and methods for insertion, search, and deletion, but standard libraries do not include built-in B-tree implementations, so third-party libraries or custom implementations are typically used.