Database 2018-02: Difference between revisions

Latest revision as of 14:14, 20 September 2018

Class Information

	Class Info
Class	ETA00137 - 데이터베이스
Lecturer	Seongjin Lee
Time and Place	407-507 Tuesday 16:00-18:00 407-507 Thursday 16:00-17:00
Office Hour	Tuesday: 18:00-19:00
Contacts	Office: 407-314
	Email: insight at gnu dot ac dot kr

Course Introduction

In Database Management System (DBMS), we study the database which is organized and structured collection of data. DBMS is a software system which acts as intermediary between user or application and the data. It allows to navigate through the data and analyze the data. In this course, we are going to learn the core mechanism that holds the system together.

Goal

In this course, we are going to learn the essence of data base management system. Students are going to learn the following concepts.

Relational model
Entity-relational model
SQL
External, conceptual, physical levels of DMBS
Data definition language, Data manipulation language, query language
Data structures
Index
Transaction and Concurrency

Text Book

Main Textbook

Not necessarily required to buy the book

Database Systems : the Complete Book (Paperback) | Garcia-Molina, Ullman 지음 |Pearson Education Asia [link ][1판 번역본 ]

Supplementary Textbook

Database Management Systems 3/E, Ramakrishnan , Gehrke, Johannes 지음 | McGraw-Hill 번역본 교보문고 바로가기
만화로 쉽게 배우는 데이터베이스, Takahashi Mana 지음, 홍희정 옮김, Azuma Shouko 그림, 성안당
데이터베이스 시스템 (AN INTRODUCTION TO DATABASE SYSTEMS), C.J. Date, Pearson, 2004

Evaluation

Categories	Ratio	Categories	Ratio
Attendance	10	Quiz	10
Assignments	10	Midterm	30
Project	10	Final	30
		Total	100%

All exams are closed book and closed notes
Any request for regrade must be made within one week of the time that the paper is returned, with no exception. You should describe in writing why the score is incorrect or graded unfairly. The written argument must be self-contained and can be evaluated based only on what is written on the paper.

Discussion

Please provide your info on this link.

All discussions and assignments are to be submitted in Piazza. Enroll into the class through the following link

Lecture Plan

#	Topic & material	Readings	Assignments
1	Course Overview and Database History [ pptx ] [ pdf ] Worksheet: DB Worksheet 1a Worksheet 1b If you haven't installed Jupyter, then please consult Jupyter Installation Guide
2	SQL Introduction Part I [ pptx ] [ pdf ] [ Notebook ][ English ] Worksheet: DB Worksheet 2a Worksheet 2b Worksheet 2c	Ch. 6	Assignment 1 Assignment 1 [English] Correct Output [English] DB for the assignment (must be unzipped) [English] Sanity checker script (run on the terminal) [English] Answer Template [English] Instructions on submitting the assignment [English]
3	SQL Introduction Part II [ pptx ] [ pdf ] [ Notebook ] Worksheet: DB Worksheet 3a Worksheet 3b Worksheet 3c	Ch. 6
4	Databas Design with ER Diagrams [ pptx ] [ pdf ] Worksheet: We are going to create an ER diagram in class with pencil and paper	Ch. 2
5	Database Design Theory Part I [ pptx ] [ pdf ] Worksheet: Worksheet 5a Closure visualization tool for python v2 / python v3	Ch. 3.2-3.7
6	Database Design Theory Part II [ pptx ] [ pdf ] Worksheet: Worksheet 6a Worksheet 6b Closure visualization tool for python v2 / python v3 Excercises on 3rd Normal Form Excercises on Multi-Valued Dependency		Assignment 2 Assignment 2 Answer Template Instructions on submitting the assignment
7	Transactions [ pptx ] [ pdf ] Worksheet:	Ch. 8.6
8	Concurrency and Locks [ pptx ] [ pdf ] Worksheet: Worksheet 8a Transaction visulization tool for pyton v2 / python v3 Transaction visulation java script	Ch. 18.1-18.4
9	Buffer Manager and Introduction to External Merge algorithm [ pptx ] [ pdf ] Worksheet: Worksheet 9a External Merge Sort Workseet Buffer manager engine for pyton v2 / python v3 Display helper Modeling java script	Ch. 11.4
10	More on External Merge Sort [ pptx ] [ pdf ] Worksheet:
11	Indexing [ pptx ] [ pdf ] Worksheet: Worksheet 11a Database for the worksheet	Ch. 13.1-13.3
12	Join part 1 [ pptx ] [ pdf ] Worksheet:	Ch. 15
13	Join part 1 [ pptx ] [ pdf ] Worksheet:	Ch. 15
14	Relational Algebra [ pptx ] [ pdf ] Worksheet: Worksheet 9a Picture used for the Worksheet Relational Algebra for pyton v2 Display helper	Ch. 2 and 16.3
15	Query Optimization [ pptx ] [ pdf ] Worksheet: Worksheet 15a Worksheet 15b Database for the worksheet Relational Algebra for pyton v2 Display helper

Working Environment Setup

Step 1: Installing Jupiter Notebook

Gentle reminder that, jupyter notebook best works at Linux

Option 1: Installation via Anaconda

It is recommended that you install Jupyter Notebook via Anaconda

Download & install Anaconda for Python here
Run jupyter notebook to confirm that it is properly installed

If Anaconda doesn't have jupyter: you can try running

conda install jupyter

Option 2: Installation via `pip`

You can also install via the python package manager pip

Make sure you have installed
- python and pip
Make sure pip is updated to its latest version
pip install --user --upgrade pip
Install Jupyter Notebook
pip install --user --upgrade jupyter

Installing other kernels and versions of python

When you are using Python3 and want to switch to Python2 in the notebook,

python2 -m pip install ipykernel

python2 -m ipykernel install —user

After restarting the Jupyter, you can chose different kernel in Jupyter notebook.

Step 2: Installing Other Dependencies

Git

Git is a version control system which we use to store the various course material; you can download from here

you can download the course material from here
If you want the up-to-date version of the course material, checkout the course repository from the git by typing the following command
- git clone https://github.com/resourceful/lecture_db YourDestination

IPython-SQL

python-sql allows you to use SQL queries inside jupyter notebooks; install using pip

pip install --user --upgrade ipython-sql

other modules

you will be needing

markdown
numpy
pandas

Step 3: Getting Started

Getting the latest course materials

You can always access the latest course materials on the course website. You can download all at once and keep them synced by using git. To get started with this, run:

git clone https://github.com/resourceful/lecture_db YourDestination

Now you should have all the materials in Database; to get the latest version, run the following command in the repository.

git pull

To read the notebook

In the directory where the relevant course materials are, run:

jupyter notebook

Course Credit

Much of the materials of this lecture is based on CS145 of Stanford.

@@ Line 56: / Line 56: @@
 |	Assignments	||	10	||	Midterm	||	30
 |-
-|	Project	||	20	||	Final	||	30
+|	Project	||	10	||	Final	||	30
 |-
 |			||		|| Total		|| 100%
@@ Line 80: / Line 80: @@
 |	style="text-align:center;"	|	1
 |	style="vertical-align: top;"|	 '''Course Overview and Database History'''
-		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day01/Day01_intro.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day01/Day01_intro.pdf pdf] ]
+		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day01/Day01_Intro.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day01/Day01_Intro.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day01/dataset_1.db DB]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day01/dataset_1.db DB]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day01/DB-WS01a.ipynb Worksheet 1a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day01/DB-WS01a.ipynb Worksheet 1a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day01/DB-WS01b.ipynb Worksheet 1b]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day01/DB-WS01b.ipynb Worksheet 1b]
 	<br>	If you haven't installed Jupyter, then please consult [[#JupyterInstall | Jupyter Installation Guide]]
 |	style="vertical-align: top;"|
@@ Line 92: / Line 92: @@
 |-
 |	style="text-align:center;"	|	2
-|	style="vertical-align: top;"|	 ''SQL Introduction Part I'''
+|	style="vertical-align: top;"|	 '''SQL Introduction Part I'''
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/Day02_SQL_p1.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/Day02_SQL_p1.pdf pdf] ]
-		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/Day02_worksheet.ipynb Notebook] ]
+		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/Day02_worksheet.ipynb Notebook] ][ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/Day02_worksheet_eng.ipynb English] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day02/dataset_1.db DB]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/dataset_1.db DB]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day02/DB-WS02a.ipynb Worksheet 2a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/DB-WS02a.ipynb Worksheet 2a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day02/DB-WS02b.ipynb Worksheet 2b]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/DB-WS02b.ipynb Worksheet 2b]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day02/DB-WS02c.ipynb Worksheet 2c]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day02/DB-WS02c.ipynb Worksheet 2c]
 |	style="vertical-align: top;"|	Ch. 6
 |	style="vertical-align: top;"|	'''Assignment 1 '''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments1/HW1.ipynb Assignment 1]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/HW1.ipynb Assignment 1]	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/en/HW1.ipynb [English]]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments1/correct_output.txt Correct Output]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/correct_output.txt Correct Output]	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/en/correct_output.txt [English]]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments1/flights.db.zip DB for the assignment (must be unzipped)]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/flights.db.zip DB for the assignment (must be unzipped)]	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/en/flights.db.zip [English]]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments1/sanity_check.py Sanity checker script (run on the terminal)]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/sanity_check.py Sanity checker script (run on the terminal)]	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/en/sanity_check.py [English]]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments1/submit.py Answer Template]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/submit.py Answer Template]	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/en/submit.py [English]]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments1/submission_instructions.txt Instructions on submitting the assignment]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/submission_instructions.txt Instructions on submitting the assignment]	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments1/en/submission_instructions.txt [English]]
 <!--	Topic	3	 -->
@@ Line 116: / Line 116: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day03/Day03_worksheet.ipynb Notebook] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day03/dataset_1.db DB]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day03/dataset_1.db DB]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day03/DB-WS03a.ipynb Worksheet 3a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day03/DB-WS03a.ipynb Worksheet 3a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day03/DB-WS32b.ipynb Worksheet 3b]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day03/DB-WS02b.ipynb Worksheet 3b]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day03/DB-WS03c.ipynb Worksheet 3c]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day03/DB-WS03c.ipynb Worksheet 3c]
 |	style="vertical-align: top;"|	Ch. 6
 |	style="vertical-align: top;"|
@@ Line 142: / Line 142: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day05/Day_05_Design_p1.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day05/Day_05_Design_p1.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day05/DB-WS05a.ipynb Worksheet 5a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day05/DB-WS05a.ipynb Worksheet 5a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day05/closure_v2.py Closure visualization tool for python v2]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day05/closure_v2.py Closure visualization tool for python v2]
-		[https://github.com/resourceful/lecture_db/raw/master/Day05/closure_v3.py / python v3]
+		[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day05/closure_v3.py / python v3]
 |	style="vertical-align: top;"|	Ch. 3.2-3.7
 |	style="vertical-align: top;"|
@@ Line 157: / Line 157: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/Day_06_Design_p2.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/Day_06_Design_p2.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day06/DB-WS06a.ipynb Worksheet 6a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/DB-WS06a.ipynb Worksheet 6a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day06/DB-WS06a.ipynb Worksheet 6b]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/DB-WS06a.ipynb Worksheet 6b]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day06/closure_v2.py Closure visualization tool for python v2]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/closure_v2.py Closure visualization tool for python v2]
-		[https://github.com/resourceful/lecture_db/raw/master/Day06/closure_v3.py / python v3]
+		[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/closure_v3.py / python v3]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day06/DB-WS-3NF.ipynb Excercises on 3rd Normal Form]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/DB-WS-3NF.ipynb Excercises on 3rd Normal Form]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day06/DB-WS-MVDs.ipynb Excercises on Multi-Valued Dependency]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day06/DB-WS-MVDs.ipynb Excercises on Multi-Valued Dependency]
 |	style="vertical-align: top;"|
 |	style="vertical-align: top;"|	'''Assignment 2'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments2/HW2.ipynb Assignment 2]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments2/HW2.ipynb Assignment 2]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments2/submit.py Answer Template]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments2/submit.py Answer Template]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Assignments2/submission_instructions.txt Instructions on submitting the assignment]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Assignments2/submission_instructions.txt Instructions on submitting the assignment]
@@ Line 186: / Line 186: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day08/Day_08_Con_lock.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day08/Day_08_Con_lock.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day08/DB-WS08a.ipynb Worksheet 8a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day08/DB-WS08a.ipynb Worksheet 8a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day08/txn_viewer_v2.py Transaction visulization tool for pyton v2]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day08/txn_viewer_v2.py Transaction visulization tool for pyton v2]
-		[https://github.com/resourceful/lecture_db/raw/master/Day08/txn_viewer_v3.py / python v3]
+		[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day08/txn_viewer_v3.py / python v3]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day08/txnViewer.js Transaction visulation java script]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day08/txnViewer.js Transaction visulation java script]
 |	style="vertical-align: top;"|	Ch. 18.1-18.4
 |	style="vertical-align: top;"|
@@ Line 200: / Line 200: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/Day_09_BM_EM.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/Day_09_BM_EM.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day09/DB-WS09a.ipynb Worksheet 9a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/DB-WS09a.ipynb Worksheet 9a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day09/EMS_Demo.ipynb External Merge Sort Workseet]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/EMS_Demo.ipynb External Merge Sort Workseet]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day09/io_backend_v2.py Buffer manager engine for pyton v2]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/io_backend_v2.py Buffer manager engine for pyton v2]
-		[https://github.com/resourceful/lecture_db/raw/master/Day09/io_backend_v3.py / python v3]
+		[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/io_backend_v3.py / python v3]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day09/display_tools.py Display helper]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/display_tools.py Display helper]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day09/compModel.js Modeling java script]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day09/compModel.js Modeling java script]
 |	style="vertical-align: top;"|	Ch. 11.4
 |	style="vertical-align: top;"|
@@ Line 226: / Line 226: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day11/Day_11_Indexes.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day11/Day_11_Indexes.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day11/DB-WS11a.ipynb Worksheet 11a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day11/DB-WS11a.ipynb Worksheet 11a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day11/complaint.db Database for the worksheet]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day11/complaint.db Database for the worksheet]
 |	style="vertical-align: top;"|	Ch. 13.1-13.3
 |	style="vertical-align: top;"|
@@ Line 236: / Line 236: @@
 |	style="text-align:center;"	|	12
 |	style="vertical-align: top;"|	 '''Join part 1'''
-		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day12/Day_12_Joins_p1.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day12/Day_12_Joins_p1.pdf pdf] ]
+		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day12/Day12_Joins_p1.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day12/Day12_Joins_p1.pdf pdf] ]
 	<br>	'''Worksheet:'''
 |	style="vertical-align: top;"|	Ch. 15
@@ Line 246: / Line 246: @@
 |	style="text-align:center;"	|	13
 |	style="vertical-align: top;"|	 '''Join part 1'''
-		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day13/Day_13_Joins_p2.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day13/Day_13_Joins_p2.pdf pdf] ]
+		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day13/Day13_Joins_p2.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day13/Day13_Joins_p2.pdf pdf] ]
 	<br>	'''Worksheet:'''
 |	style="vertical-align: top;"|	Ch. 15
@@ Line 258: / Line 258: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day14/Day_14_Algebra.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day14/Day_14_Algebra.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day14/DB-WS014a.ipynb Worksheet 9a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day14/DB-WS014a.ipynb Worksheet 9a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day14/DB-WS14a_tree.png Picture used for the Worksheet]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day14/DB-WS14a_tree.png Picture used for the Worksheet]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day14/relation_algebra_v2.py Relational Algebra for pyton v2]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day14/relation_algebra_v2.py Relational Algebra for pyton v2]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day14/display_tools.py Display helper]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day14/display_tools.py Display helper]
 |	style="vertical-align: top;"|	Ch. 2 and 16.3
 |	style="vertical-align: top;"|
@@ Line 272: / Line 272: @@
 		[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day15/Day_15_Optimization.pptx pptx] ]	[ [http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day15/Day_15_Optimization.pdf pdf] ]
 	<br>	'''Worksheet:'''
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day15/DB-WS015a.ipynb Worksheet 15a]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day15/DB-WS015a.ipynb Worksheet 15a]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day15/DB-WS015b.ipynb Worksheet 15b]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day15/DB-WS015b.ipynb Worksheet 15b]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day15/complaint.db Database for the worksheet]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day15/complaint.db Database for the worksheet]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day15/relation_algebra_v2.py Relational Algebra for pyton v2]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day15/relation_algebra_v2.py Relational Algebra for pyton v2]
-	<br>	[https://github.com/resourceful/lecture_db/raw/master/Day15/display_tools.py Display helper]
+	<br>	[http://open.gnu.ac.kr/lecslides/2018-2-DB/Lectures/Day15/display_tools.py Display helper]
 |	style="vertical-align: top;"|
 |	style="vertical-align: top;"|
 |}
@@ Line 335: / Line 334: @@
 * you can download the course material from [https://github.com/resourceful/lecture_db here]
 * If you want the up-to-date version of the course material, checkout the course repository from the <code>git</code> by typing the following command
-** <code> git checkout https://github.com/resourceful/lecture_db  </code>
+** <code> git clone https://github.com/resourceful/lecture_db YourDestination  </code>
 ==== IPython-SQL ====
@@ Line 353: / Line 352: @@
 You can always access the latest course materials on the course website. You can download all at once and keep them synced by using git. To get started with this, run:
-<code> git clone https://github.com/resourceful/lecture_db  </code>
+<code> git clone https://github.com/resourceful/lecture_db YourDestination </code>
 Now you should have all the materials in ''Database''; to get the latest version, run the following command in the repository.