DATABASE SYSTEM CONCEPTS (LOOSELEAF)
DATABASE SYSTEM CONCEPTS (LOOSELEAF)
7th Edition
ISBN: 9781260515046
Author: SILBERSCHATZ
Publisher: MCG
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Chapter 16, Problem 5PE

Explanation of Solution

To estimate the size of the r1 |><| r2 |><| r3:

  • The given relations are,
    • r1(A,B,C)
    • r2(C,D,E)
    • r3(E,F)
  • The above relations r1, r2, and r3 having the primary keys “A”, “C” and “E” respectively.
  • In relational algebra, the associative and communicative properties are exhibited using joins.
  • Hence, joining thee relations produce the same result.
  • The required size is computed as follows,
    • Perform the join of relation r1 with r2, and this result will contain 1000 records as “C” is the primary key or relation r2 and is common in two relations r1, and r2.
    • Next, perform the join operation of relation r3 with the above result and this result will contain 1000 records as “E” is the primary key for the relation r3 and is common in two relations...

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Need help answering these questions!1. Design a While loop that lets the user enter a number. The number should be multiplied by 10, and the result stored in a variable named product. The loop should iterate as long as the product contains a value less than 100.   2. Design a For loop that displays the following set of numbers: 0, 10, 20, 30, 40, 50 . . . 1000   3. Convert the While loop in the following code to a Do-While loop:     Declare Integer x = 1     While x > 0        Display "Enter a number."        Input x     End While
Need help with these:Design a While loop that lets the user enter a number. The number should be multiplied by 10, and the result stored in a variable named product. The loop should iterate as long as the product contains a value less than 100.   2. Design a For loop that displays the following set of numbers: 0, 10, 20, 30, 40, 50 . . . 1000   3. Convert the While loop in the following code to a Do-While loop:     Declare Integer x = 1     While x > 0        Display "Enter a number."        Input x     End While
Convert the While loop in the following code to a Do-While loop:    Declare Integer x = 1    While x > 0       Display "Enter a number."       Input x    End While
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