Day6Notes.md

Lecture 6 - 2/6/2023

Catya Temkin

Overview

In this lecture, we discussed Version Control Systems and useful related git commands. I will go more in depth with Centralized Systems versus Distributed Systems along with their pros and cons.

Version Control Systems

• Simplify maintaining code

Centralized Systems

• There is one unified history
  • everyone has to agree on avalible versions
  • clients just have a set of "working" files
  • to commit changes, client must reconnect to the main server
• Pros:
  1. Possible to look at past versions
  2. Simplicity of a single server
• Cons:
  1. Single server may go offline
  2. Must be connected to server to commit (need access to internet)

Distributed Systems

• Shared history
  • Clients make a copy of the systems history when checking out code
  • Clients check in/commits to their personal history
• Pros:
  1. No need for internet to commit
  2. No problem if server goes offline
• Cons:
  1. Redundancy (multiple copies of history)
  2. Potential for disagreement
     • need way to resolve conflicts and share histories
• Git is a distributed verson control system

Encoding the History of a Repository

• track the changes (delta)
  • can use tools called diff and patch
• snapshots are full copies of changed files
  • unchanged files are pointers to the previous version
• Git uses snapshots
• The Git workspace has 3 different states/loactions
  1. Working directory
  2. Staging
  3. Repository (history)
• Useful and related Git commands
  • status view current status
  • log sequence and information of past commits
  • add move from working directory to staged
  • restore --staged move from staged back to working directory
  • git commit move from staged to repository
  • reset --soft HEAD^ undo commit
  • checkout move from repository to working directory

Meme of the day