There are several types of databases that can be used depending on needs and priorities. A centralized database stores all data in one location, making organization and backups easier but potentially slowing performance from high usage. Distributed databases split data across multiple locations for faster retrieval from nearby sites, though accessing distant data can be slower and ensuring consistency is important. Horizontal and vertical partitioning further divide distributed databases by specific criteria like common fields or geographic regions. Replication copies all data to multiple locations so it can be accessed locally with changes synced to the central database during off-peak times. Central indexes link to actual data stored elsewhere to reduce updates to the main database and potentially cause delays in retrieving data. Data warehouses and data mining analyze stored information.

2. Centralised Database

3. Centralised Database A single central database accessed by multiple users + Easier to organise, edit, query and backup - Can be slower because of high usage / load

4. Distributed Database

5. Distributed Database Database split into multiple files + Data access and retrieval faster at nearest points - Can be slower accessing non local data - Need to be ensure data is consistent / synchronised

6. Distributed Database Vertical Partitioning Split the database to improve speed Group commonly queried fields together Physically closer together therefore faster to retrieve

7. Distributed Database Horizontal Partitioning Split the database according to a specific criteria Tables have exactly the same structure Organise database geographically / by region

8. Replication All data copied to all locations in the organisation Data is processed on local copies of the database Any changes copied to central database when low usage (e.g. night)

9. Central Index Database index is held centrally, which then links to actual data + Don’t store all the data in the main database so it is not frequently updated - May be a delay in retrieving data from actual database

10. Data Warehouse / Data Mining Investigate What is meant by a data warehouse What is meant by data mining

11. Credits Higher Information Systems – Using Information – Centralised and Distributed Databases Produced by M. Cunningham for the City of Edinburgh Council 2010 All images licenced under Creative Commons 3.0 Working by Aldo Gonzalez The Speed of Silence by Millicent Bystander British Isles United Kingdom by UKPhoenix79 Copy Copy Copy by David Goehring Manchester Central Library card index drawers by Frankie Roberto Old Wool Warehouse, Deal Street, Halifax by Tim Green John King Mining Monument Pinxton by Duncan Harris