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This DBMS tutorial will especially help computer science graduates in understanding the basic-to-advanced concepts related to Database Management Systems.What is a database?
READING MATERIAL: Ramakrishnan and Gehrke Chapter 1 What is a database? A database is a collection of structured data. A database captures an abstract representation of the domain of an application. Typically organized as “records” (traditionally, large numbers, on disk) and relationships between recordsWhat are the levels of abstraction in database?
Levels of Abstraction QPhysical level describes how a record (e.g., customer) is stored. QLogical level: describes data stored in database, and the relationships among the data. type customer = record name : string; street : string; c i ty : n eg r; end;What are the characteristics of conceptual database design?
The information gathered in the requirements analysis step is used to develop a higher-level description of the data. The goal of conceptual database design is a complete understanding of the database structure, meaning (semantics), inter-relationships and constraints. Characteristics of this phase are as below.