lecture3

• Before the introduction of DBMS, the file system was commonly used for data management
• File systems are still used today, especially in individual systems
• In the 1970s, file systems were used to manage data, where users saved and accessed data in the form of files
• File systems organize data into drives, folders, and subfolders in a hierarchical structure
• DBMS is used in client-server architectures where data is centralized and accessed by users worldwide
• DBMS is preferred over file systems for several reasons:
• 1. Searching Efficiency:

  • In DBMS, users can search for specific data efficiently using queries, retrieving only the necessary information
  • In contrast, file systems may retrieve entire files even for small data searches, leading to inefficiency
• 2. Metadata Handling:

  • File systems require attributes like file name, location, and permissions to access data
  • DBMS eliminates the need for such attributes, allowing users to access data without knowing its physical location
• 3. Concurrency Control:

  • DBMS provides protocols for concurrent access, ensuring data consistency when multiple users access data simultaneously
  • File systems lack such protocols, leading to potential data inconsistencies when accessed by multiple users concurrently
• 4. Security:

  • DBMS offers role-based access control, allowing different users to access only specific data based on their roles
  • File systems managed by the operating system lack hierarchical security, potentially exposing data to unauthorized users
• 5. Data Redundancy:

  • DBMS enforces constraints like primary keys and foreign keys to prevent data redundancy and ensure data integrity
  • File systems may allow storing duplicate data, leading to inefficiencies and data duplication
• DBMS is a very important system in terms of GATE exam, UGC NET exam and other competitive exams
• DBMS is a very important subject even from the interview point of view
• Database system


  Comprised of database and DBMS
• Database


  A collection of related data
• Database is not a collection of any data, it is a collection of related data