List and describe 3 Database Systems?

Analytical database

These databases store data and information extracted from selected operational and external databases. They consist of summarized data and information most needed by an organization's management and other end-users. Some people refer to analytical databases as multidimensional databases, management databases, or information databases.

These databases store detailed data needed to support the operations of an entire organization. They are also called subject-area databases (SADB), transaction databases, and production databases. For example:

• customer databases
• personal databases
• inventory databases

These are databases of local work-groups and departments at regional offices, branch offices, manufacturing plants and other work sites. These databases can include segments of both common operational and common user databases, as well as data generated and used only at a user's own site.