Q. A WINDOW into a portion of a data base is:

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Q. The E-R model is expressed in terms of:

(i) Entities
(ii) The relationship among entities
(iii) The attributes of the entities

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Q. Specialization is a ............... process.

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Q. The completeness constraint has rules:

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Q. The entity type on which the ................. type depends is called the identifying owner.

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Q. Match the following:

(i) 5 NF              (a) Transitive dependencies eliminated
(ii) 2 NF             (b) Multivalued attribute removed
(iii) 3 NF            (c) Contains no partial functional dependencies
(iv) 4 NF            (d) Contains no join dependency

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Q. The normalization of 1NF relations to 2NF involves:

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Q. Tuple in relational algebra refers to:

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Q. A relation R on a set X is said to be a partial ordering if R is

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Q. An attribute or set of attributes within one relation that matches the candidate key of some(possibly the same) relation:

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Q. With QBE, inserting records from one or more source tables into a single target table can be achieved by:

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Q. SQL command to delete a column from an existing table:

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Q. Data Scrubbing is

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Q. An attribute A of datatype varchar(20) has the value ‘xyz’, and the attribute B of datatype char(20) has the value “lmnop”, then the attribute A has ............... spaces and attribute B has ............... spaces.

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Q. Data warehouse contains ............... data that is never found in operational environment.

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Q. .................. command is used to remove a relation from SQL database.

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Q. Which of the following statement/s is/are true?

(i) Facebook has the world’s largest Hadoop Cluster.
(ii) Hadoop 2.0 allows live stream processing of Real time data.

Choose the correct answer from the code given below:

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Q. Consider the relation schema R = (A,B,C,D,E,F) on which the following functional dependencies hold:

A → B
B, C → D
E → C
D → A

What are the candidate keys of R?

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Q. Consider the following sequence of two transactions on a bank account (A) with initial balance 20,000 that transfers 5,000 to another account (B) and then apply 10% interest.

(i) T1 start
(ii) T1 A old = 20,000 new 15,000
(iii) T1 B old = 12,000 new = 17,000
(iv) T1 commit
(v) T2 start
(vi) T2 A old = 15,000 new = 16,500
(vii) T2 commit

Suppose the database system crashes just before log record (vii) is written. When the system is restarted, which one statement is true of the recovery process?

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Q. A clustering index is defined on the fields which are of type:

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