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39 votes
4 answers
2
GATE CSE 2014 Set 3 | Question: 22
A prime attribute of a relation scheme $R$ is an attribute that appears in all candidate keys of $R$ in some candidate key of $R$ in a foreign key of $R$ only in the primary key of $R$
A prime attribute of a relation scheme $R$ is an attribute that appearsin all candidate keys of $R$in some candidate key of $R$in a foreign key of $R$only in the primary ...
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33 votes
4 answers
3
GATE CSE 1994 | Question: 3.7
An instance of a relational scheme $R(A, B, C)$ has distinct values for attribute $A$. Can you conclude that $A$ is a candidate key for $R?$
An instance of a relational scheme $R(A, B, C)$ has distinct values for attribute $A$. Can you conclude that $A$ is a candidate key for $R?$
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0 votes
2 answers
4
DBMS
The correct answer is a and d. I just wanted to know that why not b and c. It is possible that it may be speed and color is also a candidate key. If you have any clarification on this let me know!!!
The correct answer is a and d. I just wanted to know that why not b and c. It is possible that it may be speed and color is also a candidate key. If you have any clarific...
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2 votes
1 answer
5
made easy test series 2023
Consider a relation R having seven attributes ABCDEFG. Fields of R contain only atomic values. FDs = {CD → G, A → BC, B → CF, E → A, F → EG, G → D} is set of functional dependencies. So, how many candidates key does the relation R have?
Consider a relation R having seven attributes ABCDEFG. Fields of R contain only atomic values.FDs = {CD → G, A → BC, B → CF, E → A, F → EG, G → D} is set of f...
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1 votes
1 answer
6
Made easy || Database
Consider a relation schema r(A, B, C, D, E, F) and attribute A is element of every candidate key of r. Maximum number of possible candidate keys of r is ________.
Consider a relation schema r(A, B, C, D, E, F) and attribute A is element of every candidate key of r. Maximum number of possible candidate keys of r is ________.
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1 votes
0 answers
7
Finding Candidate Keys | Class Practice | Unacademy
Find the candidate key(s) of the relation R(UVWXYZ) with FD set F={UV-->W, XW-->Y, U-->XZ, Y-->U} XW UV, YV, WXV YUV, XV, WV None of these
Find the candidate key(s) of the relation R(UVWXYZ) with FD set F={UV >W, XW >Y, U >XZ, Y >U}XWUV, YV, WXVYUV, XV, WVNone of these
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0 votes
1 answer
8
Test Series 2022
Please explain Ans is 22
Please explain Ans is 22
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34 votes
8 answers
9
GATE CSE 2014 Set 2 | Question: 21
The maximum number of superkeys for the relation schema $R(E,F,G,H)$ with $E$ as the key is _____.
The maximum number of superkeys for the relation schema $R(E,F,G,H)$ with $E$ as the key is _____.
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2 votes
1 answer
12
NIELIT Scientific Assistant A 2020 November: 86
A minimal super key (i.e, one of the super keys for which no proper subset is a superkey) is called: Super Key Candidate Key Primary Key Both Candidate and Primary Key
A minimal super key (i.e, one of the super keys for which no proper subset is a superkey) is called:Super KeyCandidate KeyPrimary KeyBoth Candidate and Primary Key
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4 votes
3 answers
14
NIELIT 2016 MAR Scientist B - Section C: 43
Let $R=(A,B,C,D,E,F)$ be a relation scheme with the following dependencies: $C\to F,E\to a,EC\to D, A\to B$. Which of the following is a key for $R$? $CD$ $EC$ $AE$ $AC$
Let $R=(A,B,C,D,E,F)$ be a relation scheme with the following dependencies:$C\to F,E\to a,EC\to D, A\to B$.Which of the following is a key for $R$?$CD$$EC$$AE$$AC$
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0 votes
2 answers
16
NIELIT 2016 DEC Scientist B (IT) - Section B: 36
The primary key is selected from the: Composite keys Determinants Candidate keys Foreign keys
The primary key is selected from the:Composite keysDeterminantsCandidate keysForeign keys
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0 votes
1 answer
17
NIELIT 2016 DEC Scientist B (CS) - Section B: 54
If there is more than one key for relation schema in DBMS then each key in relation schema is classified as prime key super key candidate key primary key
If there is more than one key for relation schema in DBMS then each key in relation schema is classified asprime keysuper keycandidate keyprimary key
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3 votes
2 answers
18
Made easy mock test 1 DBMS super keys
Consider the following relation R(A1, A2,...A15) with (A1,A2, ... A6) of relation R are simple candidate key. The number of possible superkey in relation R is_
Consider the following relation R(A1, A2,...A15) with (A1,A2, ... A6) of relation R are simple candidate key. The number of possible superkey in relation R is_
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2 votes
2 answers
19
ISRO2014-42
Let $x,y,z,a,b,c$ be the attributes of an entity set E. If $\{x\} ,\{x,y\}, \{a,b\},\{a,b,c\}, \{x,y,z\}$ are superkeys then which of the following are the candidate keys? $\{x,y\}$ and $\{a,b\}$ $\{x\}$ and $\{a,b\}$ $\{x,y,z\}$ and $\{a,b,c\}$ $\{z\}$ and $\{c\}$
Let $x,y,z,a,b,c$ be the attributes of an entity set E. If $\{x\} ,\{x,y\}, \{a,b\},\{a,b,c\}, \{x,y,z\}$ are superkeys then which of the following are the candidate keys...
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1 votes
2 answers
20
UGC NET CSE | June 2019 | Part 2 | Question: 35
Which of the following key constraints is required for functioning of foreign key in the context relational databases? Unique key Primary key Candidate key Check key
Which of the following key constraints is required for functioning of foreign key in the context relational databases?Unique keyPrimary keyCandidate keyCheck key
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