Data Placement

Data Placement in RDBMS:

• Data Fragmentation: Dividing the database into smaller parts (fragments) and storing them at different locations. This can be done horizontally (by rows) or vertically (by columns).
• Data Replication: Creating and storing copies (replicas) of data at multiple locations. This improves read performance and increases data availability if one site fails.
• Data Sharding: A type of horizontal fragmentation where rows of a table are held separately, on different servers. Each server acts as the single source for its subset of data.
• Data Caching: Storing frequently accessed data in a temporary, high-speed storage layer (a cache) closer to the user to reduce latency.