Introduction to DBMS
Three Schema architecture
Dbms components
Client server architecture
DBMS vs File System: DBMS eliminates data redundancy, ensures data integrity, security, supports multiple users, backup & recovery, and efficient query processing, whereas file systems lack these features.
Three-Schema Architecture: Comprises External (user views), Conceptual (community user view), and Internal (physical storage) levels with mappings ensuring data abstraction and independence.
Data Independence: Logical independence allows changes in conceptual schema without affecting external views (harder to achieve); Physical independence allows changes in physical schema without impacting conceptual schema.
DBA Role: Responsible for database setup, maintenance, security, backup/recovery, and query optimization knowledge even if not writing queries themselves.
DBMS Components: Key modules include DDL compiler (processes schema definitions), DML compiler (processes data manipulation statements), Query compiler (analyzes and optimizes queries), Runtime processor (executes operations), and Stored Data Manager (handles storage).
Real-World Design: DBMS architecture applied in systems like ticket booking and online course platforms using data abstraction and ensuring security, concurrency, and integrity.
Schema vs State: Schema defines database structure; State represents current data in the database instance.
User Types: Naive users, Application programmers, Sophisticated users (advanced querying), and DBAs, each interacting differently with the DBMS.
Brief about the advantages of Database Management System?
What is the difference between logical data independence and physical data independence? Which one is harder to achieve? Why?
Explain the functionalities of the following terms: 1) DDL compiler 2) Query Compiler 3) DML Compiler 4) Host language compiler 5) Runtime database processor 6) Stored data manager
What are the responsibilities of a DBA? If we assume that the DBA is never interested in running his or her own queries, does the DBA still need to understand query optimization? Why?
List out any five disadvantages of a file-based system.
Why do we need mapping between schema levels in three schema architecture?
Describe the three levels of data abstraction with a neat diagram.
Consider a typical online course registration system such as Coursera or Udacity. How do you enforce the concept of data abstraction and data independence by elaborating each level of abstraction with your example?
Describe briefly the function of the catalog in a DBMS. Show clearly how the catalog allows the DBMS to provide data independence and why data modelling is important?
If you were designing a Web-based system to make railway reservations and sell railway tickets, which DBMS architecture would you choose? Why? Why would the other architectures not be a good choice?
What is Data Abstraction? Explain about different views of data
List the types of Database users and discuss the roles of DBA.
Discuss the three-schema architecture used in database management. What are the key components, and how do they interact with each other? Why do we need mappings between schema levels?
Explain the difference between a database schema and a database state with a suitable example.