The document provides an introduction to GIT and compares it to SVN. It discusses the advantages of GIT such as faster performance, local repositories, and easier branching. The document outlines GIT's basic components like the working directory, staging area, and repository. It also summarizes common GIT commands for managing branches, merging, and pushing/pulling changes.

1. GIT Introduction
Raiful Hasan
DIVINE IT LIMITED

2. Objective
• Understand the advantage of GIT and determine if we should use GIT or not.
 Know how to use the common used GIT commands
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3. Subject
 Characteristic of GIT
– The most powerful features of GIT
– Explain the differences between GIT and SVN
• GIT basic usages
- Day to day GIT used commands
• Resources
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4. Characteristic of GIT
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5. History
 Invented by Linus Torvalds to support the development of the Linux Kernel
 Incredibly fast, very efficient with large projects, has an incredible branching system
for non-linear development
• Projects using Git : Linux Kernel, Perl, Eclipse, Android ...
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6. Compare to SVN
 There are many version control tools in the market But GIT is a completely difference
tool GIT own many distinct, powerful features
• Interface is fairly similar to SVN
• Git stores and thinks about data differently than SVN
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7. Compare to SVN(cont..)
SVN Data Model:
GIT Data Model:
SVN store history as a list of file-based
Database addressable by the hash value of its
changes
contents
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8. Compare to SVN(cont..)
Repository
 GIT - Local and multi Remote Repositories
SVN – only 1 repository on server
• SVN may loose history in some case, Git doesn't
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9. Compare to SVN(cont..)
5 Fundamental differences between GIT & SVN
1. GIT is distributed, SVN is not
2. GIT stores content as metadata, SVN stores just files
3. GIT branches are much more easier & fun is not the same as SVN branches.
4. GIT does not have a global revision no. like SVN do
5. GIT’s content integrity (using SHA-1 hash algorithm) is better than SVN’s.
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10. Why's GIT fast ?
• The internal database structure
 Nearly every operation is Local. Entire history is on local disk
 This database is compressed effectively transfer over network, use SSH or GIT
protocol
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11. State
• States : untracked, modified, and staged, committed
File Status Lifestyle
Untracked Unmodified Modified Staged
Edit the File
Add the File
Stage the File
Remove the File
Commit
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12. Working Area
• The Git directory, the working directory, and the staging area.
Local Operation
Working Git Directory
Staging Area
Directory (repository)
Checkout the Project
Stage Files
Commit
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13. Branch Management
 Killer feature – Managing branches. Make Git apart in the VCS community
 Branching operations nearly instantaneous. Switching back and forth between
branches just as fast
 We can create branches, and merge often even multiple times in a day
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14. Switch Branch
Point to Current Branch HEAD
master
98ca9 34ac2 f30ab
master
testing
98ca9 34ac2 f30ab
testing
Switch Branch HEAD
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15. FastForward Merge
HEAD
master
98ca9 34ac2 f30ab c2b9e
testing HEAD
Move Pointer Forward master
98ca9 34ac2 f30ab c2b9e
testing
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16. FastForward Push
 GIT “push” comand equals to svn commit. By default, GIT only allow “FastForward”
push. To override this, use --force option
C3
before push
C0 C1 C2 C4
master
public repository's master
after force push
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17. Merge vs. Rebase
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18. Merge vs. Rebase
Master C1
Merge
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19. Merge vs. Rebase
Master C2
C1
Merge
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20. Merge vs. Rebase
Master C3
C2
C1
Merge
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21. Merge vs. Rebase
Master C3 C5 Idea
C2
C1
Merge
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22. Merge vs. Rebase
Master C4 C6 Idea
C3 C5
C2
C1
Merge
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23. Merge vs. Rebase
Master C4 C6 Idea Master C4 C6 Idea
C3 C5 C3 C5
C2 C2
C1 C1
Merge Rebase
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24. Merge vs. Rebase
Merge Commit
Master C7
C4 C6 Idea Master C4 C6 Idea
C3 C5 C3 C5
C2 C2
C1 C1
Merge Rebase
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25. Merge vs. Rebase
C4’
Merge Commit
2
Master C7
C3’
1
C4 C6 Idea Master C4 C6 Idea
2
C3 C5 C3 C5
1
C2 C2
C1 C1
Merge Rebase
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26. Merge vs. Rebase
Master C4’
Merge Commit
Master C7
C3’
C4 C6 Idea Idea C6 C4
C3 C5 C5 C3
C2 C2
C1 C1
Merge Rebase
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27. Push Pull
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28. Push Pull
Computer A
Divine Server
Master
C1 C2
Computer B
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29. Push Pull
Computer A
Master git clone computerA@git.company.com:project.git
C1 C2
Divine Server
Master
Origin/Master
C1 C2
Computer B
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30. Push Pull
Computer A
Master
C1 C2
Divine Server
Master
Origin/Master
C1 C2
Computer B
Master
C1 C2
Origin/Master git clone computerB@git.company.com:project.git
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31. Push Pull
Computer A
Master git commit -a -m “ComputerA's new feature"
C1 C2 a1 a2
Divine Server
Master
Origin/Master
C1 C2
Computer B
Master
C1 C2
Origin/Master
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32. Push Pull
Computer A
Master
C1 C2 a1 a2
Divine Server
Master
Origin/Master
C1 C2
Computer B
Master
C1 C2 b1 b2
Origin/Master git commit -a -m “ComputerB's new feature"
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33. Push Pull
Computer A
Master
C1 C2 a1 a2
Divine Server
Master
Origin/Master
C1 C2
Computer B
Master
C1 C2 b1 b2
Origin/Master git push origin master
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34. Push Pull
Computer A
Master
C1 C2 a1 a2
Divine Server
Master
Origin/Master
C1 C2 b1 b2
Computer B
Master
C1 C2 b1 b2
Origin/Master git push origin master
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35. Push Pull
Master git push origin master
C1 C2 a1 a2
Divine Server
Master
Origin/Master
C1 C2 b1 b2
Master
C1 C2 b1 b2
Origin/Master
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36. Push Pull
Master git fetch
C1 C2 a1 a2
Divine Server
b1 b2 Master
Origin/Master
C1 C2 b1 b2
Master
C1 C2 b1 b2
Origin/Master
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37. Push Pull
Master git merge origin/master
C1 C2 a1 a2 a3
Divine Server
b1 b2 Master
Origin/Master
C1 C2 b1 b2
Master
C1 C2 b1 b2
Origin/Master
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38. Push Pull
Master git push origin master
C1 C2 a1 a2 a3
Divine Server
b1 b2 Master
Origin/Master
C1 C2 b1 b2
Master a1 a2 a3
C1 C2 b1 b2
Origin/Master
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39. Git Basics
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40. Installing GIT
• Address: http://git-scm.com/download
• Window, Mac – Download Installation file
 Linux - The primary Git package :
git-core, git-doc – document
git-cvs, git-svn – work with CVS, or SVN
gitk – graphical application
• $ sudo apt-get install git-core git-doc gitk git-svn
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41. Resources
More explanation why use GIT
http://whygitisbetterthanx.com
Basic tutorial
Version Control with Git - O'Reilly Media “Advance GIT”
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