Q. If D1, D2,…. Dn are domains in a relational model, then the relation is a table, which is a subset of

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Q. Given an open address hash table with load factor a < 1, the expected number of probes in a successful search is

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Q. The “PROJECT” operator of a relational algebra creates a new table that has always

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Q. The employee information of an Organization is stored in the relation:

Employee (name, sex, salary, deptname)

Consider the following SQL query

Select deptname from Employee Where sex = ‘M’ group by deptname having avg (salary) > {select avg (salary) from Employee}

Output of the given query corresponds to

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Q. For a database relation R(a, b, c, d) where the domains of a, b, c, d include only the atomic values. The functional dependency a → c, b → d holds in the following relation

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Q. Match the following:

a. Foreign keys                                  i. Domain constraint
b. Private key                                     ii. Referential integrity
c. Event control action model         iii. Encryption
d. Data security                                 iv. Trigger

Codes:
      a   b   c   d

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Q. In multiuser database if two users wish to update the same record at the same time, they are prevented from doing so by

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Q. What deletes the entire file except the file structure ?

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Q. Which command is the fastest among the following ?

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Q. B+ tree are preferred to binary tree in Database because

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Q. A Transaction Manager is which of the following ?

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Q. A B+ tree index is to be built on the name attribute of the relation STUDENT. Assume that all students names are of length 8 bytes, disk block are of size 512 bytes and index pointers are of size 4 bytes. Given this scenario what would be the best choice of the degree (i.e. the number of pointers per node) of the B+ tree ?

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Q. What is Granularity ?

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Q. Which level of Abstraction describes what data are stored in the Database ?

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Q. The problem that occurs when one transaction updates a database item and then the transaction fails for some reason is …………….

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Q. Consider a schema R(A, B, C, D) and functional dependencies A->B and C->D. Then the decomposition R1(A, B) and R2(C, D) is

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Q. A hash table has space for 75 records, then the probability of collision before the table is 6% full.

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Q. Which command classes text file, which has been created using “SET ALTERNATIVE” < FILE NAME > “Command” ?

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Q. Which of the following statements is true, when structure of database file with 20 records is modified?

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Q. The SQL Expression

Select distinct T. branch name from branch T, branch S where T. assets > S. assets and S. branch-city = DELHI,

finds the name of

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