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2 votes
2 answers
2281
Er Diagram
Consider the following entity relation diagram If A has 50 entities,B has 20 entities and C has 200 entities. what is the maximum number of triples of entities that could be in the relationship Set R ? (A) 50 (B) 100 (C) 1000 (D) 10,000 ans is A,C(given) please explain how??
Consider the following entity relation diagramIf A has 50 entities,B has 20 entities and C has 200 entities. what is the maximum number of triples of entities that could ...
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6 votes
1 answer
2282
sql query
Consider the following table Mystery Mystery A B 1 Null 2 4 3 5 Null 6 select count() from Mystery where A not in( select B from Mystery) (A) 1 (B) 0 (C) 4 (D) 3 ans is B given please explain how??
Consider the following table MysteryMysteryAB1Null2435Null6select count() from Mysterywhere A not in( select B from Mystery)(A) 1(B) 0(C) 4(D) 3ans is B givenplease expla...
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5 votes
2 answers
2285
database-indexing-2
Maximum number of clustered indices one can build for a table with n attributes, which already has a primary index?
Maximum number of clustered indices one can build for a table with n attributes, which already has a primary index?
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5 votes
1 answer
2286
database-indexing
How many different secondary indices are possible for a table with n attributes(Not necessarily at the same time)?
How many different secondary indices are possible for a table with n attributes(Not necessarily at the same time)?
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1 votes
1 answer
2288
ER model
After mapping an ER diagram relationship to Relational model using the set of rules for 1:n,m:n etc,will the achieved tables will always be in BCNF ?
After mapping an ER diagram relationship to Relational model using the set of rules for 1:n,m:n etc,will the achieved tables will always be in BCNF ?
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1 votes
2 answers
2289
Explain Division Operator
R/S is defined as ${\prod }_{R-S} (r) - {\prod }_{R-S} \begin{pmatrix} \left \langle {\prod }_{R-S} (r) \times S \right \rangle - {\prod }_{R-S,S} (r) \end{pmatrix}$ Please explain the validity of the statements with example
R/S is defined as${\prod }_{R-S} (r) - {\prod }_{R-S} \begin{pmatrix} \left \langle {\prod }_{R-S} (r) \times S \right \rangle - {\prod }_{R-S,S} (r) \end{pmatrix}$Please...
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0 votes
1 answer
2290
Self Doubt : Conflict Serializable
Account on the following statements IF Conflict Serial schedule then it is ALWAYS possible under 2PL
Account on the following statements IF Conflict Serial schedule then it is ALWAYS possible under 2PL
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2 votes
4 answers
2291
database-query-normalization-true-false
if table r has only one candidate key then which of the following is true: if R is in 3nf,it is also in bcnf R may not be in bcnf
if table r has only one candidate key then which of the following is true:if R is in 3nf,it is also in bcnfR may not be in bcnf
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4 votes
3 answers
2293
er model,databases
IF A RELATION HAS ______________ CARDINALITY, THEN NO MINIMIZATION CAN TAKE PLACE. a) 1:n b)m:m c)n:1 d) none
IF A RELATION HAS ______________ CARDINALITY, THEN NO MINIMIZATION CAN TAKE PLACE.a) 1:nb)m:mc)n:1d) none
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1 votes
1 answer
2295
UGC NET CSE | June 2010 | Part 2 | Question: 20
The PROJECT Command will create new table that has More fields than the original table More rows than original table Both (A) & (B) None of these
The PROJECT Command will create new table that hasMore fields than the original tableMore rows than original tableBoth (A) & (B)None of these
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0 votes
1 answer
2296
UGC NET CSE | June 2010 | Part 2 | Question: 19
Which data management language component enabled the DBA to define the schema components ? DML Sub-schema DLL Schema DLL All of these
Which data management language component enabled the DBA to define the schema components ?DMLSub-schema DLLSchema DLLAll of these
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1 votes
2 answers
2297
UGC NET CSE | June 2010 | Part 2 | Question: 18
Match the following : ... $\text{a-iii, b-iv, c-i, d-ii}$ $\text{a-iii, b-ii, c-iv, d-i}$
Match the following :$\begin{array}{clccl} \text{a.} & \text{2 NF} & & \text{i.} & \text{Transitive dependencies eliminated} \\ \text{b.} & \text{3 NF} & & \text{ii.} ...
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0 votes
2 answers
2298
UGC NET CSE | June 2010 | Part 2 | Question: 17
Generalization is _______ process. Top-down Bottom up Both (A) & (B) None of these
Generalization is _______ process.Top-downBottom upBoth (A) & (B)None of these
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1 votes
4 answers
2299
UGC NET CSE | June 2010 | Part 2 | Question: 16
An entity instance is a single occurrence of an ______. Entity type Relationship type Entity and relationship type None of these
An entity instance is a single occurrence of an ______.Entity typeRelationship typeEntity and relationship typeNone of these
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1 votes
0 answers
2300
Internet- restructuring of b + tree - deletion
Can someone please explain the restructuring of b+ tree in delete 15 step? I mean after 16,20,25 becomes the child of 13 ,after that it is not clear,how does 11 become the root?
Can someone please explain the restructuring of b+ tree in delete 15 step? I mean after 16,20,25 becomes the child of 13 ,after that it is not clear,how does 11 become t...
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0 votes
1 answer
2303
join
Comment on the following two statements Natural Join produce cartecian product of two tables on joing two relations with no matching coloums Full Outer Join produce cartecian product of two tables on joing two relations with no matching coloums
Comment on the following two statementsNatural Join produce cartecian product of two tables on joing two relations with no matching coloumsFull Outer Join produce cartec...
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0 votes
2 answers
2305
UGC NET CSE | December 2010 | Part 2 | Question: 18
Which of the following is an optimistic concurrency control method ? Validation based Time stamp ordering Lock-based None of these
Which of the following is an optimistic concurrency control method ?Validation basedTime stamp orderingLock-basedNone of these
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0 votes
3 answers
2307
UGC NET CSE | December 2010 | Part 2 | Question: 16
In generalisation, the differences between members of an entity is Maximized Minimized Both (A) & (B) None of these
In generalisation, the differences between members of an entity isMaximizedMinimizedBoth (A) & (B)None of these
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0 votes
4 answers
2308
#sql #dbms
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2 votes
1 answer
2309
#View Serializability #DBMS
I know that this is Conflict serializable and i know all schedules which are Conflict serializable are also view serializable But still wanted to know what is the view serializable sequence?
I know that this is Conflict serializable and i know all schedules which are Conflict serializable are also view serializableBut still wanted to know what is the view ser...
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2 votes
1 answer
2310
Deleting a node from B+ tree
How to delete key 15 from below B+ tree?
How to delete key 15 from below B+ tree?
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