What is program version management?

Version management is the recording and control of the successive versions of a program's files, so that any earlier state can be recovered and it is always clear which version is in use.

What does the repository of a version control system hold?

It holds the complete history of every file in the project rather than only the contents those files have now.

A commit is the act of recording a set of changes in the repository as one identified version, accompanied by a message describing them.

What is a working copy?

A working copy is a developer's own copy of the project files, taken from the repository, in which changes are made before being recorded.

WJEC A-Level Computer Science 601-5345-3

Hardware: Architecture, Memory and Storage

Topic overview Components of a computer system and how they connect Von Neumann architecture and the CPU The fetch-execute cycle Memory and caching Parallel processing Input and output devices and their uses Secondary storage, fragmentation and defragmentation

Networks and Data Transmission

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Logic Gates and Boolean Algebra

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Data Structures

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Organisation of Data: Files and Records

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Database Systems

Topic overview Flat files and the relational model Relational and other contemporary database systems Primary, foreign, composite and candidate keys Indexes and links between tables Entity relationship modelling Normalisation to third normal form The database management system, queries and user views

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Algorithms and Programs

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Principles of Programming

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Computing, Society and the Law

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Advanced Data Structures and Logic

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Recursion, Sorting and Searching

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Programming Paradigms and Translators

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System Design and Human-Computer Interaction

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Software Engineering Tools and Professional Practice

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Advanced Architecture and Assembly Language

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Number Representation and Floating Point

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Databases and Distributed Systems

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Operating System Management

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Software Systems and Applications

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Data Security, Cryptography and Attack

Topic overview Integrity problems in online updating The need for cryptography Symmetric and asymmetric techniques Classical ciphers and cryptographic algorithms Comparing cryptographic strength Biometric technologies Malicious software and its vectors Attacks, defence and penetration testing

Software Engineering Tools and Professional Practice

Program version management

3 things to know
A2 Unit 3

Overview

Program version management, version control system and working copy.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

What is a version control system?

Key term

What is a commit?

Key term

Why should the message accompanying a change say why it was made rather than what was changed?

Questions from this subtopic

Each one with the model answer underneath.

1
What is program version management?
Model answer
Version management is the recording and control of the successive versions of a program's files, so that any earlier state can be recovered and it is always clear which version is in use.
2
What is a version control system?
Model answer
A version control system is software that stores every recorded change to a set of files, together with who made it, when it was made and why.
3
What does the repository of a version control system hold?
Model answer
It holds the complete history of every file in the project rather than only the contents those files have now.
4
What is a commit?
Model answer
A commit is the act of recording a set of changes in the repository as one identified version, accompanied by a message describing them.
5
Why should the message accompanying a change say why it was made rather than what was changed?
Model answer
The change itself can always be read from the files, but the reason for it cannot be recovered from them afterwards.
6
What is a working copy?
Model answer
A working copy is a developer's own copy of the project files, taken from the repository, in which changes are made before being recorded.

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