Register

Recent questions tagged candidate-key

4 votes
4 answers
34
Random Doubt, Candidate Key, DBMS
If A Relation R(A,B,C,D) and CK given is (AB,C) and FD is given as A->C Then the relation is in which highest normal form?
If A Relation R(A,B,C,D) and CK given is (AB,C)and FD is given as A->C Then the relation is in which highest normal form?
User Avatar
3 votes
2 answers
36
Test by Bikram | Databases | Test 2 | Question: 4
A relation $R(P,Q,R,S)$ has $\{PQ, QR, RS, PS\}$ as candidate keys. The total number of superkeys possible for relation $R$ is ______
A relation $R(P,Q,R,S)$ has $\{PQ, QR, RS, PS\}$ as candidate keys. The total number of superkeys possible for relation $R$ is ______
User Avatar
3 votes
1 answer
37
previous year question
R(A,B,C,D,E,F,G,H) A->BC B->CFH CH->G E->A A->EG what is the number of candidate key
R(A,B,C,D,E,F,G,H)A->BCB->CFHCH->GE->AA->EGwhat is the number of candidate key
User Avatar
0 votes
1 answer
38
Test by Bikram | Mock GATE | Test 3 | Question: 25
Consider these relations : $R = ABCDE$ $A\rightarrow BC$ $B\rightarrow E$ $D\rightarrow E$ What is the candidate key for the above relations? CA AB BD AD
Consider these relations :$R = ABCDE$$A\rightarrow BC$$B\rightarrow E$$D\rightarrow E$What is the candidate key for the above relations?CAABBDAD
User Avatar
0 votes
1 answer
39
Gate Practice Question
A relational schema R with attributes (ABCDEFG).It is known that D never appears on RHS of any FD.How many different possibilities are there for what a Candidate key of R can be.?
A relational schema R with attributes (ABCDEFG).It is known that D never appears on RHS of any FD.How many different possibilities are there for what a Candidate key of R...
User Avatar
0 votes
1 answer
40
No of Candidate key
Given relation R(A, B, C, D, E) and set of functional dependencies F = {AB → C, AB → D, D → A, BC → D, BC → E} Number of candidate key in the following relation have?
Given relation R(A, B, C, D, E) and set of functional dependencies F = {AB → C, AB → D, D → A, BC → D, BC → E}Number of candidate key in the following relatio...
User Avatar
0 votes
1 answer
42
testbook
User Avatar
5 votes
3 answers
43
Number of minimal candidate keys
A relation R(A,B,C,D,E,F) holds following FDs $AB\rightarrow C$ $C\rightarrow D$ $D\rightarrow EA$ $E\rightarrow F$ $F\rightarrow B$ The number of minimal candidate keys of R are _______.
A relation R(A,B,C,D,E,F) holds following FDs$AB\rightarrow C$$C\rightarrow D$$D\rightarrow EA$$E\rightarrow F$$F\rightarrow B$The number of minimal candidate keys of R a...
User Avatar
2 votes
2 answers
46
ISRO2014-42
Let $x,y,z,a,b,c$ be the attributes of an entity set E. If $\{x\} ,\{x,y\}, \{a,b\},\{a,b,c\}, \{x,y,z\}$ are superkeys then which of the following are the candidate keys? $\{x,y\}$ and $\{a,b\}$ $\{x\}$ and $\{a,b\}$ $\{x,y,z\}$ and $\{a,b,c\}$ $\{z\}$ and $\{c\}$
Let $x,y,z,a,b,c$ be the attributes of an entity set E. If $\{x\} ,\{x,y\}, \{a,b\},\{a,b,c\}, \{x,y,z\}$ are superkeys then which of the following are the candidate keys...
User Avatar
33 votes
4 answers
47
GATE CSE 1994 | Question: 3.7
An instance of a relational scheme $R(A, B, C)$ has distinct values for attribute $A$. Can you conclude that $A$ is a candidate key for $R?$
An instance of a relational scheme $R(A, B, C)$ has distinct values for attribute $A$. Can you conclude that $A$ is a candidate key for $R?$
User Avatar
39 votes
4 answers
49
GATE CSE 2014 Set 3 | Question: 22
A prime attribute of a relation scheme $R$ is an attribute that appears in all candidate keys of $R$ in some candidate key of $R$ in a foreign key of $R$ only in the primary key of $R$
A prime attribute of a relation scheme $R$ is an attribute that appearsin all candidate keys of $R$in some candidate key of $R$in a foreign key of $R$only in the primary ...
User Avatar
33 votes
3 answers
50
GATE CSE 2014 Set 2 | Question: 22
Given an instance of the STUDENTS relation as shown as below ... $(\text{StudentName, StudentAge})$ to be a key for this instance, the value $X$ should NOT be equal to______.
Given an instance of the STUDENTS relation as shown as below$$\begin{array}{|c|c|c|c|c|} \hline \textbf {StudentID} & \textbf{StudentName} & \textbf{StudentEmail} & \text...
User Avatar
34 votes
8 answers
51
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 _____.
User Avatar
Page: