Q. Given a Relation POSITION (Posting-No, Skill), then query to retrieve all distinct pairs of posting-nos requiring skill is

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Q. If a relation with a Schema R is decomposed into two relations R1 and R2 such that (R1 ∪ R2) = R1 then which one of the following is to be satisfied for a lossless joint decomposition (---> indicates functional dependency)

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Q. Which level of Abstraction describes how data are stored in the data base ? 

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Q. Third normal form is based on the concept of ______.

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Q. The student. marks should not be greater than 100. This  is

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Q. GO BOTTOM and SKIP-3 commands are given one after another in a database file of 30 records. It shifts the control to

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Q. An ER Model includes
1. An ER diagram portraying entity types.
II. Attributes for each entity type
III. Relationships among . entity types.
IV. Semantic integrity constraints that reflects the business rules about data not captured in the ERdiagram.

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Q. Based on the cardinality ratio and participation______________associated with a relationship type, choose either the Foreign Key Design, the Cross Referencing Design or Mutual Referencing Design.

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Q. Data Integrity control uses _______________

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Q. Consider the following schemas
Branch = (Branch-name, Assets, Branch-city)
Customer = (Customer-name, Bank name, Customer-city)
Borrow = (Branch~name, loannumber, customer account-number)
Deposit = (Branch-name, Accountnumber,
Customer-name, Balance)
Using relational Algebra, the Query that finds customers who have balance more than 10,000 is_______

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Q. Find the false statement :

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Q. Consider the table:

Student (stuid, name, course, marks)
Which one of the following two queries is correct to find the highest marks student in course 5 ?

Q.1. Select S.stuid From student S Where not exists  (select * from student e where e.course = '5' and e.marks ≥s.marks)

Q.2. Select s.stuid From student S Where s.marks >any (select distinct marks from student S where s.course =5)

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Q. Armstrong (1974) proposed systematic approach to derive functional dependencies. Match the following w.r.t. functional dependencies:

a.Decomposition Rule (i)   If X →Y and Z →W then {X, Z} → {Y, W}

b. Union Rule (ii)  If X →Y an  {Y,W} → Z then {X, W} → Z

c. Composition Rule (iii) If X →Y and X →Z then X → {Y, Z}
 
d. Pseudo transitivity Rule (iv) If X →{Y,Z} and  {Y,W} → Z then X → Y and  X →Z

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Q. Match the following:
List - I                                         List - II

a. Secondary                          i.    Functional Dependency
Index

b. Nonprocedural                  ii.  B-Tree
Query
Language

c. Closure of                           iii. Relational Algebraic
set of                                                Operation
Attributes

d.  Natural                              iv. Domain Calculus
JOIN

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Q. The best normal form of relation scheme R(A. B, C, D) along with the set of functional dependencies F = {AB → C, AB → D, C → A, D → B} is

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Q. Identify the minimal key for relational scheme R(A, B, C, D, E) with functional dependencies F = {A → B, B → C, AC → D}

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Q. Division operation is ideally suited to handle queries of the type :

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Q. What kind of mechanism is to be taken into account for converting a weak entity set into strong entity set in entity-relationship diagram?

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Q. Which of the following is true?

I.  Implementation of self-join is possible in SQL with table alias.

II. Outer-join operation is basic operation in relational algebra.

III. Natural join and outer join operations are equivalent.

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Q. Which of the following is correct?

I. Two phase locking is an optimistic protocol.
II. Two phase locking is pessimistic protocol
III. Time stamping is an optimistic protocol.
IV. Time stamping is pessimistic protocol.

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