Register

NIELIT 2018-55

• recategorized by
3,359 views

3 Answers

4 votes
4 votes
Maximum number of super keys are 8 because X is a key and if any one is included with key it will be a super key.

We have two choices for each one (Y,Z,W) include it and don't include it. making it as 2^3=8

Correct answer is B
User Avatar
2 votes
2 votes
We know that definatly a X is a super key. So from pending Y,Z,W maximum number of super keys can be $2^3 - 1 = 7$ and As X is a key then 7+1 = 8 is max number of super key
User Avatar
1 votes
1 votes
Maximum no. of possible superkeys for a table with n attributes = 2^(n-1)
Here, n = 4.
So, the possible superkeys = 2^(4-1) = 2^3 = 8
The possible superkeys are : X, XY, XZ, XW, XYZ, XYW, XWZ, XYZW
User Avatar
Voting & Accepting an answer helps improve the community
Answer:
← PreviousNext →
← Previous in categoryNext in category →

Related questions

1 votes
1 votes
2 answers
1
Arjun asked Dec 7, 2018
2,007 views
NIELIT 2018-34
Identify the true statement from the given statements: Number of child pointers in a B/B+ tree node is always equal to number of keys in it plus one B/B+ tree is defined by a term minimum degree. And minimum degree depends on hard disk block size, key and address size (1) (1) and (2) (2) None of these
Identify the true statement from the given statements:Number of child pointers in a B/B+ tree node is always equal to number of keys in it plus oneB/B+ tree is defined by...
User Avatar
2 votes
2 votes
3 answers
2
Arjun asked Dec 7, 2018
968 views
NIELIT 2018-36
______ is NOT a part of the ACID properties Inconsistency Consistency Atomicity Isolation
______ is NOT a part of the ACID propertiesInconsistencyConsistencyAtomicityIsolation
User Avatar
1 votes
1 votes
2 answers
3
Arjun asked Dec 7, 2018
1,368 views
NIELIT 2018-42
____ symbol is used to denote derived attributes in ER model Dashed ellipse Squared ellipse Ellipse with attribute name underlined Rectangular Box
____ symbol is used to denote derived attributes in ER modelDashed ellipseSquared ellipseEllipse with attribute name underlinedRectangular Box
User Avatar
4 votes
4 votes
3 answers
4
Arjun asked Dec 7, 2018
3,689 views
NIELIT 2018-49
The following table has two attributes $X$ and $Y$ where $X$ is the primary key and $Y$ is the foreign key referencing $X$ ... $(4,3)$ and $(6,4)$ $(2,4)$ and $(7,2)$ $(3,2)$ and $(9,5)$ $(3,4), (4,5)$ and $(6,4)$
The following table has two attributes $X$ and $Y$ where $X$ is the primary key and $Y$ is the foreign key referencing $X$ with on-delete cascade.$\begin{array}{|c|c|} \h...
User Avatar
Link Copied!