EBK DATABASE SYSTEM CONCEPTS
7th Edition
ISBN: 9781260049268
Author: SILBERSCHATZ
Publisher: MCG COURSE
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Chapter 3, Problem 32E
Explanation of Solution
Query:
The query for the given scenario:
SELECT distinct teaches.ID, Name FROM takes, teaches, instructor WHERE teaches.course_id = takes.course_id AND instructor.Id = teaches.Id and Grade is not NULL AND teaches.ID not in (SELECT distinct teaches.Id FROM takes, teaches WHERE teaches.course_id = takes.course_id and Grade="A");
Explanation:
- The subquery(inner select query) finds teacher Id's who have given Grade "A" in any course that they teach...
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Students have asked these similar questions
Question D.4: FIFO Page Replacement
Consider the following page reference string:
e, c, b, e, a, g, d, c, e, g, d, a
Considering 4 frames, fill in the following table and then answer how many page faults would occur with the
FIFO page replacement algorithm.
RS: reference string; FO: frame 0, F1: frame 1, etc.
Hint: all frames are initially empty, so your first unique pages will all cost one fault each.
Time
1234567891011
12
RS
e
cb
e agd ce g d
a
FO
F1
F2
F3
Page fault?
b) Total # page faults:
c) Briefly (1-2 sentences) explain Belady's Anomaly that can occur in FIFO Page Replacement.
Consider a system that uses a fixed-partition scheme, with equal partitions of size 2" bytes, and the main
memory has 2¹8 bytes. A process table is maintained with a pointer to the resident partition for each resident
process. How many bits are required for the pointer in the process table? Show all your steps.
Use the same semaphore notation shown above to describe how we can ensure the execution order of the
following process execution graph:
P6
P2
P7
P1
P3
P4
P5
Use all of the following semaphores in your answer:
s1=0; s2=0; s3=0; s4=0; s5=0; s6=0;
Chapter 3 Solutions
EBK DATABASE SYSTEM CONCEPTS
Ch. 3 - Prob. 1PECh. 3 - Prob. 2PECh. 3 - Prob. 3PECh. 3 -
Suppose that we have a relation marks(ID, score)...Ch. 3 - Suppose that we have a relation marks(ID, score)...Ch. 3 -
The SQL like operator is case sensitive (in most...Ch. 3 - Prob. 7PECh. 3 - Prob. 8PECh. 3 - Prob. 9PECh. 3 - Prob. 10PE
Ch. 3 - Prob. 11ECh. 3 - Prob. 12ECh. 3 - Prob. 13ECh. 3 -
Consider the insurance database of Figure 3.17,...Ch. 3 - Prob. 15ECh. 3 - Prob. 16ECh. 3 - Prob. 17ECh. 3 - Prob. 18ECh. 3 -
List two reasons why null values might be...Ch. 3 - Prob. 20ECh. 3 - Prob. 21ECh. 3 - Prob. 22ECh. 3 - Prob. 23ECh. 3 - Prob. 24ECh. 3 - Prob. 25ECh. 3 - Prob. 26ECh. 3 - Using the university schema, write an SQL query to...Ch. 3 - Prob. 28ECh. 3 - Prob. 29ECh. 3 - Prob. 30ECh. 3 - Prob. 31ECh. 3 - Prob. 32ECh. 3 - Prob. 33ECh. 3 - Prob. 34ECh. 3 - Prob. 35E
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