3i Infotech Placement: Sample Questions 959 - 960 of 1245

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Question 959

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Describe in Detail

Essay▾

What is Relational Algebra?

Explanation

Structure of Relational Algebra in DBMS
  • The relational algebra is a theoretical procedural query language which takes instance of relations and does operations that work on one or more relations to describe another relation without altering the original relation.
  • So, both the operands and the outputs are relations, and so the output from one operation can turn into the input to another operation which allows expressions to be nested in the relational algebra.
  • The relational algebra is a relation-at-a-time (or set) language where all tuples are controlled in one statement without the use of loop.
  • There are several variations of syntax for relational algebra commands and you use a common symbolic notation for the commands and present it informally.
  • The primary operations of relational algebra are as follows:
    • Select
    • Project
    • Union
    • Set different
    • Cartesian product
    • Rename

Question 960

Question

MCQ▾

Emile receives a flat weekly salary of ₹ 240 plus 12 % commission of the total volume of all sales he makes. What must his rupees volume be in a week if he is to make a total weekly of ₹ 540?

Choices

Choice (4)

a.

₹ 3,600

b.

₹ 2,500

c.

₹ 6,480

d.

₹ 2,880

Answer

b.

Explanation

Emile receives a flat weekly salary of ₹ 240 plus 12 % commission of the total volume of all sales he makes.

He weekly makes a total of ₹ 540.

We are asked to find the total volume Emile is receiving. Let it be x Rupees.

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