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+2 votes

Consider the following three tables R, S and T. In this question, all the join operations are natural joins ($\bowtie$). ($\pi$) is the projection operation of a relation:

Possible answer tables for this question are also given as below:

  1. (a)
  2. (b)
  3. (c)
  4. (d)
in Databases by Veteran (103k points)
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2 Answers

+2 votes
Best answer
A) option is option return all possible results after natural join but it does not involve the table t during natural join so false

In b )option record  5 6 4 and record 1 2 2 not possible in result so false

In c) option record 5 2 4 abd record 1 6 2 nit possible after natural join of table .

In d) option it contain partial result after joining all three table

So d option should be answer
by Boss (19.9k points)
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What is the resulting table of πA,B(R⨝T) ⨝ πB,C(S⨝T) ?

this line is missing from question

0 votes
Option A is the correct one..
by (11 points)

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