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0 votes
1 answer
1591
Dbms relational model
What are the difference b/w E R model and relational model ????? Please discuss it in detail. Why we need ER model ?
What are the difference b/w E R model and relational model ?????Please discuss it in detail.Why we need ER model ?
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5 votes
3 answers
1592
#testseries
Consider the following E-R diagram: What is the minimum relations required which satisfied the 2nd normal form? A) 1 B) 2 C) 3 D) 4
Consider the following E-R diagram: What is the minimum relations required which satisfied the 2nd normal form?A)1B)2C)3D)4
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2 votes
1 answer
1593
Transaction Management
Which of the following protocols does not ensure conflict serializability and safety from deadlocks? Graph based protocols Two-phase locking protocol Time-stamp ordering protocol Both a & b
Which of the following protocols does not ensure conflict serializability and safety from deadlocks?Graph based protocolsTwo-phase locking protocolTime-stamp ordering pro...
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2 votes
2 answers
1594
ER model doubt
How is it opt D ?
How is it opt D ?
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0 votes
0 answers
1597
SQL check operator
Create table Student(Rno numeric, Name varchar(20),Marks numeric, Course varchar(30)); In order to ensure that the value of Marks should not exceed 100, which of the following should be used?( Marks: -0.33 ) Alter(Marks>=100) Alter(Marks<100) Check (Marks>=100) Check(Marks<100)
Create table Student(Rno numeric, Name varchar(20),Marks numeric, Course varchar(30));In order to ensure that the value of Marks should not exceed 100, which of the follo...
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1 votes
2 answers
1600
Normalization
True or false , 1)minimal canonical cover may not be unique. 2) canonical cover may not be unique
True or false , 1)minimal canonical cover may not be unique.2) canonical cover may not be unique
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4 votes
2 answers
1601
B+ tree
pls explain
pls explain
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2 votes
2 answers
1602
ER model
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1 votes
1 answer
1603
Test Series
a) I, III b) I, IV c) II, III d) II, IV
a) I, IIIb) I, IVc) II, IIId) II, IV
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2 votes
1 answer
1604
Relational Algebra
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4 votes
4 answers
1606
Normal forms conceptual
Consider a relation R(ABCD) is decomposed into R1(AC), R2(BD) based on some set of functional dependencies then R1 and R2 definitely be in _______________ Normal Form.
Consider a relation R(ABCD) is decomposed into R1(AC), R2(BD) based on some set of functional dependencies then R1 and R2 definitely be in _______________ Normal Form.
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1 votes
1 answer
1609
max index blocks
Database file consists of 10,000 records with record size 100 bytes , block size 512 bytes.If sparse B+ tree index built over given database file with serach key size 22B, both block and record pointer size 12B each.Max index blocks req if node order P is defined as pointers per node ________________
Database file consists of 10,000 records with record size 100 bytes , block size 512 bytes.If sparse B+ tree index built over given database file with serach key size 22B...
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3 votes
1 answer
1610
Canonical cover
FDs are : A->C AC->D E->AD E->H Find : i) Number of FDs in canonical form. i) Number of FDs in minimal form.
FDs are :A->CAC->DE->ADE->HFind :i) Number of FDs in canonical form.i) Number of FDs in minimal form.
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4 votes
3 answers
1611
serial schedule
Ques2:how many serial schedule view equal to schedule (s)?
Ques2:how many serial schedule view equal to schedule (s)?
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5 votes
1 answer
1612
number of superkey
consider the following relational schema R(ABCDE) .The number of super keys in relation R if every two attributes of relation R is candidate keys are ___________
consider the following relational schema R(ABCDE) .The number of super keys in relation R if every two attributes of relation R is candidate keys are ___________
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1 votes
0 answers
1616
block nested query
please cjheck this
please cjheck this
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1 votes
2 answers
1617
madeeasy work book
T1: r1(A) r1(B) w1(B) T2:r2(A) r2(B) w2(B) 1)how many concurrent schedules between t1 and t2? 2) how many non serial achedule are serializable? 3) how many schedules serializable as T1-->T2 Am not getting how to find all these. please someone help me. thanku in advance
T1: r1(A) r1(B) w1(B)T2:r2(A) r2(B) w2(B)1)how many concurrent schedules between t1 and t2?2) how many non serial achedule are serializable?3) how many schedules serializ...
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1 votes
2 answers
1618
minimum relation which satisfy 1nf
the number of minimum relation which satisfy1 nf (partial participation between E1 and R should not lost in RDBMS design )
the number of minimum relation which satisfy1 nf (partial participation between E1 and R should not lost in RDBMS design )
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