{"id":5264,"date":"2026-01-21T12:32:21","date_gmt":"2026-01-21T07:02:21","guid":{"rendered":"https:\/\/w3buddy.com\/?post_type=cposts&p=5264"},"modified":"2026-01-21T12:32:23","modified_gmt":"2026-01-21T07:02:23","slug":"fundamentals-first","status":"publish","type":"cposts","link":"https:\/\/w3buddy.com\/blog\/notes\/oracle-database-architecture\/fundamentals-first\/","title":{"rendered":"FUNDAMENTALS FIRST"},"content":{"rendered":"\n

What is Data?<\/strong><\/h3>\n\n\n\n

Data<\/strong> = Raw facts without context
Example: “25”, “John”, “2024-12-21”<\/p>\n\n\n\n

What is Information?<\/strong><\/h3>\n\n\n\n

Information<\/strong> = Data with context\/meaning
Example: “John is 25 years old and joined on 2024-12-21”<\/p>\n\n\n\n

What is Database?<\/strong><\/h3>\n\n\n\n

Database<\/strong> = Organized collection of structured data stored electronically<\/p>\n\n\n\n

    \n
  • Eliminates data redundancy<\/li>\n\n\n\n
  • Ensures data integrity<\/li>\n\n\n\n
  • Enables concurrent access<\/li>\n\n\n\n
  • Provides security and backup<\/li>\n<\/ul>\n\n\n\n

    What is DBMS (Database Management System)?<\/strong><\/h3>\n\n\n\n

    DBMS<\/strong> = Software to create, manage, and access databases
    Examples: Oracle, MySQL, PostgreSQL, SQL Server<\/p>\n\n\n\n

    What is RDBMS (Relational DBMS)?<\/strong><\/h3>\n\n\n\n

    RDBMS<\/strong> = DBMS based on relational model (tables with rows\/columns)<\/p>\n\n\n\n

      \n
    • Uses SQL for data manipulation<\/li>\n\n\n\n
    • Enforces ACID properties (Atomicity, Consistency, Isolation, Durability)<\/li>\n\n\n\n
    • Oracle is an RDBMS<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n

      INTERVIEW QUESTIONS:<\/strong><\/p>\n\n\n\n

      Q1: What’s the difference between data and database?<\/strong>
      A:<\/strong> Data is raw facts. Database is an organized collection of related data stored systematically with relationships, constraints, and metadata for efficient retrieval and management.<\/p>\n\n\n\n

      Q2: Why use a database instead of flat files?<\/strong>
      A:<\/strong> Databases provide:<\/p>\n\n\n\n

        \n
      • Data integrity through constraints<\/li>\n\n\n\n
      • Concurrent access control<\/li>\n\n\n\n
      • ACID transactions<\/li>\n\n\n\n
      • Efficient querying (indexes)<\/li>\n\n\n\n
      • Security and access control<\/li>\n\n\n\n
      • Backup\/recovery mechanisms<\/li>\n\n\n\n
      • No data redundancy<\/li>\n<\/ul>\n\n\n\n

        Q3: What are ACID properties?<\/strong>
        A:<\/strong><\/p>\n\n\n\n

          \n
        • Atomicity:<\/strong> Transaction is all-or-nothing<\/li>\n\n\n\n
        • Consistency:<\/strong> Database moves from one valid state to another<\/li>\n\n\n\n
        • Isolation:<\/strong> Concurrent transactions don’t interfere<\/li>\n\n\n\n
        • Durability:<\/strong> Committed data survives system failures<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

          What is Data? Data = Raw facts without contextExample: “25”, “John”, “2024-12-21” What is Information? Information = Data with context\/meaningExample: “John is 25 years old and joined on 2024-12-21” What is Database? Database = Organized collection of structured data stored electronically What is DBMS (Database Management System)? DBMS = Software to create, manage, and access […]<\/p>\n","protected":false},"template":"","meta":{"googlesitekit_rrm_CAowu461DA:productID":""},"categories":[952,1241],"class_list":["post-5264","cposts","type-cposts","status-publish","hentry","category-notes","category-oracle-database-architecture"],"_links":{"self":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/cposts\/5264","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/cposts"}],"about":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/types\/cposts"}],"wp:attachment":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/media?parent=5264"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/categories?post=5264"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}