Block 2 Flashcards
What is the definition of Lifecycle?
**Lifecycle - The process of analysing designing and then implementing software**
What are the different stages in the software lifecycle
- System analysis - understanding and defining the system needs to do
- System Design - Describing in text, drawing and digraming how the system and its components should be
- Implementation - programming and developing the documentation
- Validation - Testing for bugs and wether ite meets the requirements
- Maintenance - Modifying and upgrading after installation and operation
What are the different methodologies of software development
What are the different requirements of system dev?
- Functional requirements
- What systems must do
- Non-functional requirements
- How a system must do it
- Constraints and qualities of a system
- Include usability, performance, maintainability, security and legal constraints
Identify which requirements are functional and non-funtional
- Functional
- Non-Functional
- Functional
- Non-Functional
- Non-Functional
- Functional
What are the steps in system analysis?
- Gather Requirements
- Look at business processes, activities and transactions
- Look at documents
- Look at existing systems
- Look at the current market
- Analyse Requirements
- Specify Requirements
- Validate Requirements
What does an analyst do?
- Understand and communicate with clients/users
- To establish business / user needs
- Strong technical backgrounds allowing for technical requirements to be made
Explain this graph
****Requirements is the most crucial part that allows for better and easier developments****
What is a statement scope?
- Agree on scope of the system
- High level overview of deliverables
- Agree on what will not be in the system
- Agreements to protect the developers to avoid external requests
What is ATOMs statment scope?
The function of the ATOM sales order system is to manage the transaction process between a customer placing an order through final payment. WILL NOT include stock management function
What are use Cases?
- Describes interactions between a user to see a goal
- User will interact, system will respond
- In a swquence of steps
- What the user does
- What the system should do in response
- The FUNCTIONAL REQUIREMENTS
What are the different components on use cases?
- Primary Actor - Customer
- Goal - Aim of funtion
- Scope - Use cases
- Main Sequence - Interactions between systems and user
What are the different use case types?
Interactions with software - Business use case
Actor to the business itself (description of a system that automates a process)
Buisness organisation + processes - System use case
**Actor to internal system**
What are use Cases?
- A goal
- Used in requirements and analysis stage of system dev lifecycle
- Describes user / stakeholder (primary actor) system interactions
- To achieve a goal
- Describes the sequence of steps and system behaviour during interactions
- Can includes supporting actors which can be systems
- When external support required
- Which will have their own goals that need to be met too
- Can includes supporting actors which can be systems
How do you layout use cases?
Make a goal list for an ATM transaction
What is a business use case?
What is a system use case?
What is the different levels of use case detail?
- Basic (Casual) use case
- Detailed (Fully dressed) use case
- The further a project processes, the more detailed use cases are needed
What is a general use case?
Contains
- Primary Actor
- Goal
- Scope/goal
- Main Success Sequence
What is a fully dresses use case?
Contains base use cases
- Primary Actor
- Goal
- Scope
- Main Success Sequence
Contains Further detail as well
- Supporting actors - Other employees + stakeholders
- Stakeholder - something or someone with a vested interest in the behaviour or outcome of the use case
- Triggers
- Preconditions
- Guarantees (Success + Minimum)
What are ATOMs stakeholders and intrests?
What are triggers?
Triggers
- Event that initiates the use case
- What causes the actor to start it
What are pre-conditions?
- What must be true before the use case can occur
- Assumptions about the state of the world
- Things that have happened already
What is the pre-conditions and triggers of ATOM?
What are guarentees?
What are extensions/exceptions?
- Events that can go differently or wrong
- Forsights that should be taken into account during system design
- So proper reposes are created
- Like system prompts instead of crashing
- Hardest part of use cases
- Biggest contribution to require analysis
- Added after main sequence in a use case template
- Which includes guarantees too
What are the different extensions conditions that apply to ATOM?
How do you add an extension?
What are the extension handlers for these conditions in ATOM
What are guarantees?
- Outcomes of what must be true after use case occurrence
- Success guarantee
- Use case succeeds - main sequence → success guarantees
- Minimum guarantee
- Extensions → minimum guarantees
What are the components of a fully-dressed use case template?
What can UML diagrams be used for?
- Use cases can be represented as UML diagrams
- Unified modelling langaguage
- System Design Diagram Standard
- Requires narratives to be used effectively
How does consistency and completness apply to analysis and design?
- Consistency + Completeness used to assess that analysis and design is fit for purpose
- Consistency → Are entires in different parts of the use case consistent
- Completeness → for any step is there another use case that provides relevant data
What are use case rules?
- Description of user behaviour and interaction with users
- Communicating device between all stakeholders involved in system development
- Detailed and complex as needed
- NOT user interfaces
- Functional requirements
- Leads to success or known failure
What is system design?
- How a system should be made
- Uses diagrams drawings and text
To design:
- Overall architecture
- User databases
- User interfaces
- Programs
What is database design?
- Information system
- Collections of programs and a data storage structure
- Essential for data needs identification + data storage
What are entities?
- Type of thing that an org wants to hold data
- Can be people like stend or lecturer or online platforms
What are attributes and the different types of attributes?
- Data we need to know and collect
Student_name, student_ID, Student_DOB
**Simple Attributes**
- AKA atomic attributes
Student id
********Composite attributes********
- Many parts
**Name = title + initial + surname**
**Single-valued OR Multivalued attributes**
**Derived attributes**
- Attributes taken from a process involving
What is an attribute domain?
Set possible values of an attributes
******The domain of the attribute month could be January, Febuary******
What are relationships?
- Two or more entities linked to one another
- Lecture teaches module
How do you represent entities and relationships?
What is the entity relationship diagram
What is cardinality?
How do you represent cardinalities with a number?
How do keys and realtionships work with entity relationship diagrams?
primary keys - Attribute that uniquely identify an entity
key - create relationships between entities
1→many relationships - Primary key form the one end is added as foreign key in the many end
1→1 - both ends may have the same primary keys
What is the relationship diagram for ATOM?
What is design?
- Database Design
- Struct of the data
- Explore what data needs to be stored and how
- Entity, attributes and relationship identifications
What do ERD’s not tell us?
- Shows static structure of data
- Doesnt show changes in data
- Events and states are required
Give an exmaple of events, states and entities?
What are events?
- Something that happens in the environment
- Causes entities to transition from one state to another
- Needs ****either or both**** response and recording
What are events
- Something that happens in the environment
- Causes entities to transition from one state to another
- Needs ****either or both**** response and recording
**********What are the events and response in a sales order for ATOM?************
What are states?
- Recognisable period in the life of an object
- Different states =
- Different capabilities
- Different constraints
- Different characteristics
- Object remains in a state until triggered by an event
What is the different notation for states and transitions?
What is a transitent state?
What is a guard/guarded transition?
What are state diagram?
- Represents different states in the life of a Data Entity
- Could describe all aspects of the systems behaviour and its sequence of events
- Computer programs
- UI dialogues
- Business process (Sales Order)
What the state diagram for this process?
What are activities?
- Ongoing process (state) of performing some action
- Rep using activity diagrams
- Shows ordering of activities and transitions between them
- Shows concurrent activities, responsibilities and dataflows
- Transitions are timeless
What are the uses of activity diagrams?
- Sequencing of a Business Use Case
- Business work flows and responsibilities
- Sequence of System Use Cases
What is UML notation?
What is advanced notation UML?
What is the UML diagram for this sequence for a buisness process?
