What are the main approaches to increasing database throughput and scalability?

Main approaches to increasing database throughput and scalability:

1. Sharding — horizontal partitioning of data into parts (shards) stored on different servers. This reduces the load on each individual server and increases overall throughput.

2. Replication — creating copies of the database to distribute read load. Writes usually go to the master server, and reads are served from replicas.

3. Caching — using external caches (e.g., Redis, Memcached) to store frequently requested data, reducing load on the database.

4. Query and index optimization — proper index design and SQL query optimization to reduce execution time.

5. Using connection pools — reduces overhead associated with establishing connections to the database.

6. Vertical scaling — increasing server resources (CPU, RAM, SSD), but with limits.

7. Using specialized DBMSs — for example, NoSQL for certain data types and workloads.

The application of these approaches depends on specific requirements and the architecture of the application.