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1644
2769
4263
5283
0524
0709
1318
1644
1971
2348
2769
3326
3684
3900
4263
4547
4904
5283
To
cylinder
1
To
cylinder
2
To
cylinder
6
To
cylinder
10
question in part a. Start each of parts a and b
from the figure shown.)
4. A hashed file has space for 70 records. Relative
record numbers of 0-69 label each of the 70 record
positions. In addition, there is space for several
overflow (synonym) records. Draw a picture of the
file and, using the division-remainder method, store
records with each of the following four digit keys,
taking collisions into account as necessary:
a. 4000.
b. 5207.
c. 0360.
d. 1410.
5. Consider the following relational database that Best
Airlines uses to keep track of its mechanics, their
skills, and their airport locations. Mechanic number,
airport name, and skill number are all unique fields.
Size is an airport's size in acres. Skill Category is the
type of skill, such as an engine skill, wing skill, tire
skill, etc. Year Qualified is the year that a mechanic
first qualified in a particular skill; Proficiency Rating
is the mechanic's proficiency rating in a particular
skill.
SKILL Table
Skill Number
Skill Name
Skill Category
QUALIFICATION Table
Mechanic
Skill
Year
Proficiency
Number
Number
Qualified
Rating
Analyze each of the following situations and,
using the physical database design techniques
discussed in this chapter, state how you would
modify
the
logical
design
shown
to
improve
performance or otherwise accommodate it.
a. There is a high-priority need to quickly find any
particular airport's data given only the airport's
city and state.
b. There is a frequent need to find the total salary
of all of the mechanics at any particular airport.
c. There is a high-priority need to quickly find any
particular mechanic's data together with the data
about the airport at which she works.
d. There is a frequent need to list the names and
telephone numbers of the mechanics who work at
any particular airport, together with the airport's
city and state.
e. Assume that there is an additional attribute
called Skill Description in the SKILL table. This
attribute is used to store lengthy descriptions of
each skill. The problem is that its presence in the
SKILL table is slowing down access to the rest
of the data in the table, which is accessed much
more frequently.
MECHANIC Table
Mechanic
Mechanic
Airport
Number
Name
Telephone
Salary
Name
AIRPORT Table
Airport
Year
Name
City
State
Size
Opened
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