Comparing Two Set Of Functional Dependencies
Duration: 7 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- Paper 1 | Reasoning Test: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Puzzle Solving (Puzzles), Venn Diagram, Analogy, Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Selection Decision Table (Decision Making), Logical Sequence Of Words, Cubes & Dices, Analytical Reasoning (Counting Figures Reasoning), Calendar, Alphabet and Word Tests, Numerical Reasoning, Number System, Averages, Mixtures and Alligation, Percentages, Series Completion, Analogy and Classification, Patterns in Two-Dimensional Figures, Coding and Decoding, Mathematical Operations, Direction Sense, Algebra, Logical Deduction and Induction, Syllogisms and Venn Diagrams, Critical Reasoning, Order, Ranking and Sequence, Reading Comprehension, Profit, Loss and Discount, Constraint Puzzles, Speed, Time and Distance, Traverse Surveying, Ratio and Proportion, Time and Work, Mensuration, Permutations and Combinations, Clocks and Calendars, Data Interpretation, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Cubes and Dice, Vocabulary, Blood Relations, Data Sufficiency
- Paper 1 | Numerical Analysis: Number System, HCF LCM, Percentage, Ratio and Proportion (Ratios), Average, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Algebra, Statistics, Data Interpretation, Mental Ability, Arithmetic, Logarithm, Profit and Loss, Simple Interest and Compound Interest, Speed Time and Distance, Mixture and Alligation, Mensuration and Geometry, Permutation and Combination, Probability, Sequences and Series, Powers, Surds and Logarithms, Subject-Verb Agreement, Sentence Completion, Geometry, Sentence Structure and Correction, Data Sufficiency, Trigonometry, Measurement and Quantity Take-Off, Signal Space and Optimum Detection, Probability, Statistics, Algebra, Time and Work, Speed, Time and Distance, Data Interpretation, Graph Theory, Combinatorics
- Paper 1 | General Knowledge: State Wise GK, History, Geography, GK- Current Affairs, Static General Knowledge, Polity, Indian Economy
- Paper 1 | DBMS: 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, Relational Calculus, Database Security & Authorization, Database Recovery
- Paper 1 | Data Communication & Network: 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, Network Security, Security in Mobile and Wireless Computing, Input Output Organisation, File Management, Hardware Basics, Terms & Abbreviations, Protocols & Services, Network Access Technologies, Cyber Safety and Security, Basics of COA
- Paper 2 | System Analysis & Design: Fundamentals of Systems and Information Systems, SDLC and Development Approaches, Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Security, Risk Management & Maintenance, extras
- Paper 2 | Programming Language (Java): Java Fundamentals, OOPS with Java, Array, String, IO & References, Generic & Collections, Multithreading, Java, Miscellaneous, Control Flow, OOPS with C++, Stack, C Fundamentals, Arrays & Pointers, Object Oriented Technology, Control Flow & Looping, Introduction to Python
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The video lecture covers the application of attribute closure to determine the equivalence of two sets of functional dependencies (FDs). The instructor defines equivalence as having identical closures ($F_1^+ = F_2^+$) but proposes a more practical method: checking if $F_1 \subseteq F_2^+$ and $F_2 \subseteq F_1^+$. He demonstrates this with a specific example involving a relation R(ACDEH) and two sets of FDs, F and G. By calculating attribute closures for the left-hand side attributes of each FD in both sets, he verifies that every FD in F is implied by G and vice versa, concluding that the sets are equivalent.
Chapters
0:00 – 2:00 00:00-02:00
The lecture begins with the title 'APPLICATION OF ATTRIBUTE CLOSURE' and the topic 'Equivalence of Two FD sets'. The instructor explains that two functional dependency sets, $F_1$ and $F_2$, are equivalent if their closures are identical ($F_1^+ = F_2^+$). He notes that calculating full closures is impractical due to their infinite nature. Instead, he introduces a practical condition: $F_1 \subseteq F_2^+$ and $F_2 \subseteq F_1^+$. This means every FD in one set must be derivable from the other. He draws a diagram showing $F_1$ and $F_2$ as subsets of each other's closure to visualize this mutual implication.
2:00 – 5:00 02:00-05:00
The instructor presents a problem with relation $R(ACDEH)$ and two sets of FDs: $F = \{A ightarrow C, AC ightarrow D, E ightarrow AD, E ightarrow H\}$ and $G = \{A ightarrow CD, E ightarrow AH\}$. He sets up the verification by writing the conditions $F \subseteq G$ and $G \subseteq F$. He starts checking $F \subseteq G$ by calculating the closure of attributes in $F$ using rules in $G$. For $A$, $(A)^+_G = ACD$, confirming $A ightarrow C$ and $AC ightarrow D$. For $E$, $(E)^+_G = ACDEH$ (using $E ightarrow AH$ and $A ightarrow CD$), confirming $E ightarrow AD$ and $E ightarrow H$. He marks these checks with red checkmarks on the board.
5:00 – 7:13 05:00-07:13
The instructor completes the verification by checking the reverse condition, $G \subseteq F$. He calculates the closure of $A$ under $F$. Using $A ightarrow C$ and $AC ightarrow D$, he finds $(A)^+_F = ACD$, confirming $A ightarrow CD$. Next, he calculates $(E)^+_F$. Using $E ightarrow AD$ and $E ightarrow H$, he gets $EADH$, then adds $C$ via $A ightarrow C$ to get $(E)^+_F = ACDEH$. This confirms $E ightarrow AH$ is implied by $F$. Since both subset conditions are satisfied, he concludes the sets are equivalent ($F = G$) and writes the final equality on the board.
The video provides a clear, step-by-step guide on verifying the equivalence of two sets of functional dependencies using attribute closure. The instructor first establishes the theoretical basis, explaining why direct closure comparison is difficult and introducing the subset method. He then applies this method rigorously to a concrete example, calculating closures for specific attributes to prove that every dependency in one set is implied by the other. The lesson concludes with a definitive proof of equivalence, reinforcing the importance of attribute closure in database normalization and schema design.

