DBMS PRACTICE QUESTIONS

Duration: 5 min

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Module outline

  1. About the course: About the Course
  2. Mathematical Aptitude: Number System, HCF LCM, Divisibility Rules, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Time and Work, Mensuration and Geometry, Simple Interest and Compound Interest, Speed Time and Distance, Age Problems, Mixture and Alligation, Algebra, Powers and Exponents (Surds and Indices), Pipe and Cistern, Trigonometry, Statistics, Data Interpretation, Arithmetic
  3. Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Analogy, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Seating Arrangements, Syllogisms, Venn Diagram, Puzzle Solving (Puzzles), Logical Sequence Of Words, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Analytical Reasoning (Counting Figures Reasoning), Cubes & Dices, Calendar, Clock
  4. General Knowledge: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, GK- Current Affairs, Static General Knowledge
  5. Art of Teaching: Nature, Objectives & Characteristics of Teaching, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Classroom Management & Communication, Teaching-Learning Aids & ICT Integration, Evaluation, Assessment & Measurement, Professional Development & Ethics, Policies, Acts & Contemporary Issues, Curriculum & School Environment, Guidance, Counselling & Mental Health, Inclusive Education & Special Needs, Micro-Teaching & Teaching Skills, Lesson Planning
  6. Environmental Science: Environment
  7. Unit 1 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  8. Unit 2 | COA: Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Programming the Basic Computer
  9. Unit 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  10. Unit 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  11. Unit 4 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  12. Unit 5 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
  13. Unit 6 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control
  14. Unit 7 | Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer
  15. Unit 8 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  16. Unit 9 | Object Oriented Programming: OOPS with C++
  17. Unit 10 | Web Development: HTML Basics, CSS, JavaScript-Basics, XML
  18. Unit 11 | Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines
  19. Unit 12 | IoT: Emerging Tech Trends, Cloud Computing
  20. Unit 13 | Artificial Intelligence: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms
  21. Unit 14 | E-Commerce: Electronic Data Interchange and E-Commerce, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Physical Security and Cryptography Basics, Cyber Safety and Security
  22. Unit 15 | Multimedia: Multimedia
  23. Unit 16 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  24. Full Length Mock Tests — General Paper:
  25. Full Length Mock Tests — Computer Science (Paper II):
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video is an educational lecture on database theory, specifically focusing on the process of finding candidate keys for a relational schema. The problem presented is R(WXYZ) with a set of functional dependencies: X -> W, WZ -> XY, and Y -> WXZ. The instructor systematically applies the attribute closure method to determine which attribute sets can function as candidate keys. He begins by testing individual attributes and small combinations, calculating their closures to see if they encompass all attributes in the relation. The lecture progresses from identifying obvious keys to using heuristics for finding multiple candidate keys, culminating in a final list of keys.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor starts by writing the problem statement "Q. R(WXYZ) Find candidate key" and listing the functional dependencies: X -> W, WZ -> XY, and Y -> WXZ. He begins the analysis by calculating the closure of X, denoted as X+, which he writes as {X, W}. He notes that this is not a superkey because it lacks Y and Z. Next, he calculates the closure of the combination WZ, writing (WZ)+ = {W, X, Z, Y}. He identifies this as a Super Key (SK) and a Candidate Key (CK). He then checks the subsets W and Z, writing W+ = {W} and Z+ = {Z}, marking them as not keys. Finally, he calculates the closure of Y, writing Y+ = {Y, W, X, Z}, identifying Y as a Candidate Key. He summarizes the candidate keys found so far as {Y, WZ}.

  2. 2:00 – 4:30 02:00-04:30

    The instructor moves on to discuss finding multiple candidate keys. He writes a rule on the board: "To find multiple CKs: X -> PA then X must be apart of any CK". He identifies the Prime Attributes (PA) as {W, Y, Z}. He then explores the combination XZ. He reasons that since X -> W, the set XZ can derive WZ. Since WZ -> XY, XZ can derive all attributes. He writes "CK {Y, WZ, XZ}" on the board. He also writes "X -> Y" and crosses out "X -> W", possibly correcting a dependency or exploring a relationship, but the final boxed answer clearly lists Y, WZ, and XZ as the candidate keys. He boxes the final answer "CK {Y, WZ, XZ}" to conclude the problem.

The lecture provides a clear, step-by-step demonstration of finding candidate keys using attribute closure. It covers the initial identification of keys through direct calculation and then introduces a heuristic method to find additional keys involving prime attributes. The instructor uses board writing to visually track the closure calculations and the final set of candidate keys, ensuring students can follow the logical progression from functional dependencies to the final solution.

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