Code 401: Class 04 - Data Modeling

Questions

Better overall code quality
Time savings at deployment that offsets the upfront time investment of creating the tests
Reduction in defect rates

beforeEach() Runs a function before each test to prep something for the test afterEach() Runs after every test which allows a developer to run a subsequent function to perform a clean up task after the test
The primary downside of test driven development is that there are significant upfront time costs.
ES6 Classes vs. Constructor/prototype classes primary difference is that classes can extend parent classes which is not possible with standard constructors
ReST (Representative State Transfer protocol) allows transfer of additional information to be transferred over http in terms of pseudo states

Functional programming concept regarding programming using pure functions, preventing side-effects, and reducing mutability
Object-oriented Programming (OOP)
- Encapsulation individual object’s state is kept private in a class, public methods allow for interaction
- Abstraction mechanism that allows for high level interaction
- Inheritance child classes are allowed to use all fields of its parent class as well as add its own
- Polymorphism allows a child class to be treated exactly like its parent class
Class a template for assembling objects
Super keyword used to link a child class to its parent
This keyword that refers to the particular instance in question
Jest a JavaScript testing framework
Continuous Integration (CI) a development method where frequent smaller code updates are automatically tested and deployed
ReST Representational State Transfer protocol
Data model an abstract representation of real world data in an organized fashion

SQL (Structured Query Language)
SQL is relational
SQL must fit schema
MongoDB / NoSQL
- Name comes from Humongous
- No strict schema
- Much more flexible
- No relations
- Collections built of documents which look like json
Big companies often use both
At very large scale SQL cannot scale horizontally and may hit a theoretical processing limit

SQL known as relational databases, NoSQL are non-relational or distributed
NoSQL are document based instead of table based
Complex queries are better suited to SQL
NoSQL is better suited to hierarchical data
NoSQL preferred for big data
MongoDB NoSQL that stores data in json like documents with dynamic schema
- Very quick for simple queries
- Horizontally scalable
- Dynamic schema allows changes to the schema without modifying all existing data

NoSQL data modeling often starts with application-specific queries
Designed to answer the question “What questions do I have?”
May require better understanding of data structures
Good for hierarchical or graph-like data
Denormalization can lead to greater total data volume but more efficient querying