Description
Introduction
The objective of this assignment is to learn storing information and designing data structure on external memories.
What you must do
Assume that we have a relation Employee(id, name, bio, manager-id). The values of id and manager-id are integers each with the fixed
size of 8 bytes. The values of name and bio are character strings and take at most 200 and 500 bytes, respectively. Note that as opposed to
the values of id and manager-id, the sizes of the values of name and bio are not fixed and are between 1 to 200 (500) bytes. The size of
each page is 4096 bytes (4KB). The size of each record is less than the size of a page. Using the provided skeleton code with this
assignment, write a C++ program that stores relation Employee and access its records in a single file on the external storage, i.e., hard disk.
Your program must first read an input Employee relation and store in a new file on disk. The input relation is stored in a CSV file, i.e., each
tuple is in a separate line and fields of each record are separated by commas. Your program must assume that the input CSV file is in the
current working directory, i.e., the one from which your program is running, and its name is Employee.csv. We have included an input
CSV file with this assignment as a sample test case for your program. Your program must create the new file and store and access
records on the new file correctly for other CSV files with the same fields as the sample file.
Your program must store the records of the input CSV file in a new file with the name EmployeeRelation on the current working directory.
You may use one of the methods explained for storing variable-length records and the method described on storing pages (blocks) of
variable-length records in our lectures on storage management to store records and pages. They are also explained in Sections 9.7.2 and
9.6.2 of Cow Book, respectively.
6/1/23, 1:03 AM Homework: Storage & Buffer Management (w4)
https://canvas.oregonstate.edu/courses/1939345/assignments/9237574?module_item_id=23191649 2/3
During the file creation, your program may keep up to three pages (blocks) in main memory at any time. The submitted solutions that use
more main memory will not get any points.
After finishing the file creation, your program should accept an Employee id in its command line and search the file for all records of the
given id. Like file creation, your program may use up to three pages in main memory at any time. The submitted solutions that use more
main memory will not get any points for implementing this lookup operation. The user of your program may search for records of multiple
ids, one id at a time.
Each student has an account on hadoop-master.engr.oregonstate.edu server, which is a Linux machine. Your should ensure that your
program can be compiled and run on this machine. You can use the following bash command to connect to it:
> ssh your_onid_username@hadoop-master.engr.oregonstate.edu
Then it asks for your ONID password and probably one another question. To access this server, you must be on campus or connect to the
Oregon State VPN.
You can use following commands to compile and run C++ code:
> g++ -std=c++11 main.cpp -o main.out
> main.out
Necessary files
Input file: Employee.csv (https://canvas.oregonstate.edu/courses/1939345/files/99013991?wrap=1)
(https://canvas.oregonstate.edu/courses/1939345/files/99013991/download?download_frd=1)
Following files contain the skeleton code to generate the required EmployeeRelation file. You may make changes to these files adhering to
the assignment requirements.
main.cpp (https://canvas.oregonstate.edu/courses/1939345/files/99014006?wrap=1)
(https://canvas.oregonstate.edu/courses/1939345/files/99014006/download?download_frd=1)
(https://canvas.oregonstate.edu/courses/1939345/files/99014006?wrap=1) classes.h
(https://canvas.oregonstate.edu/courses/1939345/files/99014014?wrap=1)
6/1/23, 1:03 AM Homework: Storage & Buffer Management (w4)
https://canvas.oregonstate.edu/courses/1939345/assignments/9237574?module_item_id=23191649 3/3
Total Points: 10
Storage & Buffer Management
Criteria Ratings Pts
10 pts
(https://canvas.oregonstate.edu/courses/1939345/files/99014014/download?download_frd=1)
What to turn in
The assignment is to be turned in before Midnight (by 11:59pm) on May 3. You may turn in the source code of your program through Canvas.
The assignment may be done in groups of two students. Each group may submit only one file that contains the full name, OSU email, and
ONID of every member of the group.
Grading criteria
The program must follow the guidelines on organizing records in pages and the limits on the number of pages in main memory. It must also
return correct answers for search queries. The programs that do not implement the record and page data structures according the guidelines
given in the lecture will not get any points. Partial implementations will get partial credits. The programs that do not follow memory limitation
requirements do not get any points. The programs that implement the aforementioned restrictions but do not answer any query from our test
set correctly will get only minimum (1-2) points. The programs that answer some search queries correctly and fail on others will get partial
credits.
Description of
criterion
10 pts
Full
Marks
9 pts
Minor Error
Your program doesn’t work properly if
the ID is not in Employee.csv file.
6 pts
Partial Credit
Some queries were
returned correctly.
2 pts
Major Error
Your program do not
return any queries
correctly
0 pts
No Marks
You did not meet the
assignment requirements