Q. An entity has:

(i) a set of properties
(ii) a set of properties and values for all the properties
(iii) a set of properties and the values for some set of properties may non-uniquely identify an entity
(iv) a set of properties and the values for some set of properties may uniquely identify an entity

Which of the above are valid?

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Q. Aggregation is:

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Q. Suppose R is a relation schema and F is a set of functional dependencies on R. Further, suppose R1 and R2 form a decomposition of R. Then the decomposition is a lossless join decomposition of R provided that:

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Q. In a heap, every element is …………… of all the elements in the subtree.

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Q. A superkey for an entity consists of:

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Q. Which of the following set of keywords constitutes a mapping in SQL?

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Q. If a relation is in 2NF then:

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Q. Which of the following is true ?

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Q. Consider the query : SELECT student_name FROM student_data WHERE rollno (SELECT rollno FROM student_marks WHERE SEM1_MARK=SEM2_MARK);

Which of the following is true?

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Q. A primary key for an entity is:

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Q. Aggregate functions in SQL are:

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Q. If a relation is in 2NF and 3NF forms then:

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Q. The end of an SQL command is denoted by:

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Q. Consider  the  query  :  SELECT  student_name  FROM  students  WHERE class_name=(SELECT  class_name  FROM  students  WHERE  math_marks=100); what will be the output ?

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Q. Which of the following statements is wrong?

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Q. A recursive foreign key is a:

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Q. A sub class having more than one super class is called:

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Q. A relation R={A,B,C,D,E,F} is given with following set of functional dependencies:

F={A→B,AD→C,B→F,A→E}.

Which of the following is Candidate Key?

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Q. Which statement is false regarding data independence?

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Q. In DBMS, deferred update means:

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