This short course introduces you to JAVA programming language by covering the very basics and is suitable for any beginner. The student will be taken through concepts of Object Oriented Programming to more advanced topics such as Multi threading and File management. By learning this module, you will   

• Be introduced to concepts of Object Oriented Programming
• Be able to debug errors using various concepts such as Exception Handling
• Be introduced to new features of the latest version of JAVA 

• Help you clock in 300+ hours of coding for a wide range of problems
• Teach you how scalable web/desktop applications are built
• Expose you to what top tech companies expect from developers

A database is an organized collection of structured information, or data, typically stored electronically in a computer system. A database is usually controlled by a database management system (DBMS). Together, the data and the DBMS, along with the applications that are associated with them, are referred to as a database system, often shortened to just databases. Data within the most common types of databases in operation today is typically modeled in rows and columns in a series of tables to make processing and data querying efficient. The data can then be easily accessed, managed, modified, updated, controlled, and organized. Most databases use structured query language (SQL) for writing and querying data. After completing this course, you will have

• Complete knowledge of entities and relationships
• Knowledge on how to design your database and how to query data from it
• Knowledge on various types of databases

Java Web Application is a very dynamic programming software used to build websites. It offers support for web applications through JSPs and Servlets. We can build a website with static HTML web pages but when we want data to be dynamic, we require a web application. Java is the name used for both, the programming language that can be used for building complex web applications and for the software platform that used this programming language as its most essential component. It is widely used by development companies to build secure, robust and scalable web applications. In this course, we will be teaching you the knowledge that is required for a beginner to become an adept JAVA professional. You will further be given challenges and projects to reinforce your knowledge. In the course you will learn

• Why exactly should one learn JAVA?, JSP and Servlets
• How to connect to MySQL and what a Spring is?
• Hibernate and Springboot
• Security and deployment of you web application.
• Other technologies like- Kafka, Redis and JMS
• Connection with MongoDB

Scalability of a system is generally the ability of a system to adapt to change and allocate resources. When a retail website is started, their market reach would be generally small. With time, the website’s reach grows. As it reaches more people, the incoming traffic to the website increases. This puts a strain on the website's existing system which was initially designed to cater a small number of customers. So, this calls for scaling the system based on the demand. In this course you will be learning concepts such as Distributed Systems, Scalable Architecture and Design Patterns. At the end of the course you will be having a project where you will be expected to put forth the skills and knowledge you have gained from the course.

• Introduction to scalable systems and distributed systems
• Common design patters such as Creational patterns, Structural patterns, and Behavioral patterns
• Master slave database and database sharing.
• Pub-Sub pattern and Saga pattern

During the course of this week, you will be learning how to structure your webpage using HTML5. HTML5 is a programming language whose acronym stands for HyperText Markup Language. It allows the modification of the appearance of web pages. It is also used to structure and present content for the websites.

The topics taught in this week are:

• Valid document structure, anatomy of HTML syntax
• HTML5 semantic tags - Elements and attributes, Block and inline elements
• Essential HTML5 tags - headings, paragraph, styles, comments, colours
• HTML lists - unordered and ordered lists
• Inserting images using HTML 
• How to create hyperlinks using anchor tags
• HTML tables
• HTML forms and create a simple contact me form
• HTML Div-Layout and separate content for CSS styling
• Classes, ID
• HTML iFrames
• HTML Graphics
• HTML Media
• HTML APIs- Geolocation, Web Storage, Web Workers, Drag and Drop, SS Event
• HTML best practices- HTML vs XHTML

During this week, you will learn how to style your webpage. Styling a web page is vital as it impacts how the audience perceives your brand, product, or service. The first impression that they have on your website can make either stay on your page or migrate them to a competitor’s. This is where Cascaded Style Sheets(CSS) come into play.

During this week, you will learn:

• Basics of CSS3, CSS rules
• Comments, Colors, background, border, margin, padding, height and width
• CSS selectors and properties
• Inline, internal, and external CSS
• Font styling, web safe fonts - texts, icons, links
• The 'Box model'
• CSS sizing methods
• CSS static, relative, and absolute positioning systems
• CSS float and clear 
• Pseudo classes and pseudo elements
• Class vs. ID
• Opacity, Navigation bars, Dropdowns
• CSS rule conflict resolution. specificity, and implementing style hierarchy
• Images and forms styling
• Transitions, animations, pagination, 2D and 3D transforms
• Responsive web design 
• The grid system
• Flexbox, media queries
• CSS coding best practices

As the number of devices that are available to the general populace increases, your website will receive traffic from various forms of devices. Each of these devices has different screen sizes, different UIs, and other differing features. So, it is vital that you ensure that your website looks best regardless of the device it is viewed from. During the classes this week, you will learn about Bootstrap4. Bootstrap is an open-source front-end framework for faster and easier web development. It includes HTML and CSS based design templates for typography, forms, buttons, tables, navigation, models, image carousels and many other, as well as optional JavaScript plugins.

This week’s content will have:

• The mobile-first paradigm
• Wireframes in the design phase
• Twitter Bootstrap- Grid System
• How to install the Bootstrap framework
• Bootstrap containers to layout website easily
• Other Bootstrap components- buttons, tables, images, jumbotron, alerts, progress bars, spinners, dropdowns, forms, panels, modal, tooltip, popover, scrollspy, utilities, media objects and filters
• Bootstrap carousels
• Bootstrap cards 
• Bootstrap navigation bars
• Bootstrap themes
• Font awesome

A good User Interface (UI) is almost invisible to the user. It avoids unnecessary clutter and gets straight to the point. This is done by using a myriad of labels and visual aids. However, the most vital feature for a good UI are common UI elements. By integrating common elements in your UI, the users will feel more comfortable and will be able to get things done more quickly.

During the course of this week, you will learn:

• Web Design - Colours, typography
• Principles of a good User Interface (UI)
• Principles of a good User Experience (UX)
• Usability- Don’t make the user think
• Naturalness
• User Control
• Predictability
• Flexibility and efficiency
• Consistency
• Error prevention
• Clarity
• Visual hierarchy
• Progressive disclosure
• Accommodate all types of users
• Fitts' law
• Protect the user’s work
• Design for interaction
• Focus on one action
• Grouping and breakup
• Prioritise performance
• Principles-
  • DRY
  • KIS
  • Less is more
  • Responsive Web Design (RWD).
• Information architecture
• User research and usability testing
• Improving accessibility
• Implementing these principles on our website.

The most common usage for a website is in E-commerce. In general, an eCommerce website is considered to be highly dynamic with a lot of elements. That is why the student is being introduced to this particular type of website. It will help them handle almost any type of website thereafter.

During this week we will teach you how to:

• Interact with clients for creating their eCommerce website
• Building the website front end from scratch with the help of wireframes
• Code walkthrough

This week we will be taking our website to the next level with interactivity and reaction to page events such as page load, button clicks, mouse movements, keyboard input etc. We’ll dynamically alter the contents and style of a webpage. A big advantage of having a website which is actively interacting with the user is more user engagement. This will give more leads and in turn more revenue.

The topics we will be covering in detail during this week are:

• Variables, data types, operators in JavaScript 
• Statements, syntax, comments, and events
• Loops, control, and conditionals 
• JS forms
• Document Object Model (DOM)
• Browser Object Model (BOM)
• JS functions
• Scope and closures 
• Object-Oriented Programming (OOP) 
• JS objects and prototypes- keyword
• Cookies
• Exception handling
• Arrow functions
• Promises
• Template string, default parameters, spread and rest operators, destructuring, generators, set, map, weak set, weakmap 
• HTML APIs
• Separation of concerns, refactoring, debugging, and coding best practices

In computer programming, refactoring is generally done to improve the design, structure, and/or implementation of the software. All these actions are done while preserving its functionality.

During this week we will learn about:

• Installing and using the jQuery framework
• jQuery syntax, selectors, events and functions
• Manipulate text, styles and attributes with jQuery
• Create animations and customizations with jQuery
• Responding to user-initiated events with jQuery
• Traversing - ancestors, descendants, siblings, filtering

We will learn how to code your eCommerce website with the help of JavaScript. The importance of JavaScript as a web technology can be determined from the fact that it is currently used by 94.5% of all websites. As a client-side programming language, JavaScript helps web developers to make web pages dynamic and interactive by implementing custom client-side scripts. The topics we will be discussing are 

• Possibilities with JS 
  
• Animating our website
• Code walkthrough

We will be learning how to serve and retrieve data using 3 data types- AJAX, JSON and XML.

We will be covering:

• Serving and retrieving data to a web site
• Asynchronous loading - Set up and handle AJAX requests and responses. 
• JSON
• XML
• Processing JSON data
• JSON vs. XML

Now that we have covered the major parts of the course, we will now be moving on to the concluding week.

During this week, we will be 

• Building final parts of the eCommerce site UI
• Adding asynchronous calls to the website and Data transfer using JSON
• Summary
• What next?
• Motivational tips

This will be the second week of the course. During this week, we will be giving emphasis on different concepts which are paramount to be a good Java Developer. The concepts taught in this week are very important as they will be the foundation of modern programming using Java. Here, you will be learning-

• Encapsulation and Abstraction
• Classes and Objects
• Constructors
• The "this" pointer
• The Static and final keyword
• Access Modifiers
• Inheritance (is-a relationship)
• Composition (has-a relationship)
• Abstract classes and Interfaces
• Method overloading and Overriding
• Polymorphism

This is the final week of the course. In this week we will be looking into more advanced topics which are essential to build more complex programs. You will be using the knowledge from the previous week and the current week in your final project. During this week, you will be learning-

• Packages
• Exception Handling
• Multithreading
• File Handling, I/O and networking

• Arrays
  • Static arrays
  • Dynamic arrays
  • 2D arrays, row-major and column-major mapping, matrices
• Strings
• LinkedList
  • Singly LinkedList and its operations
  • Doubly LinkedList and its operations
  • Circular LinkedList and its operation

A tree is a non-linear data structure where data objects are organized in terms of hierarchical relationships. Java provides two in-built classes, TreeSet and TreeMap, in Java Collection Framework that cater to the needs of the programmer to describe data elements in the aforesaid form. There are many different types of tree structures available and we’ll be discussing them one by one

• Trees.
  • Binary trees, their representations.
  • Pre-order, In-order, post-order traversals
  • Binary search trees
  • AVL trees

   

Heap and Trie are a special case of trees. A Heap is a special tree-based data structure in which the tree is a complete binary tree. Trie is an efficient information retrieval data structure. Using Trie, search complexities can be brought to the optimal limit. In the session, we will try to solve the longest word in the dictionary problem using Tries.

• Graphs
  • Types of graphs
  • Breadth-first search, depth-first search
  • Topological sort
  • Shortest path problem
    
    • Dijkstra's algorithm
    • Bellman–Ford algorithm
• Minimum spanning tree problem
• • Prim's algorithm
  • Kruskal's algorithm
• Disjoint Sets

• Sorting- 
  • Types of sorting techniques
  • Bubble sort
  • Insertion sort
  • Selection sort
  • Quick sort
  • Merge sort
  • Heap sort
  • Count sort
  • Bucket sort
  • Radix sort
  • Shell sort

  
  

• Searching
  • Linear search
  • Binary search
• Hashing
  • Hash function
  • Collision handling
    • Chaining
    • Open addressing
      • Linear probing, primary clustering
      • Quadratic probing, secondary clustering
• Double hashing

• Types of algorithms
• Greedy Algorithms
  • Strategy of Greedy Algorithms
  • Elements of Greedy Algorithms
  • Advantages of Greedy Algorithms
  • Disadvantages of Greedy Algorithms
  • Applications of Greedy Algorithms
  • Knapsack Problem
  • Job sequencing with deadlines
  • Huffman coding

The divide and conquer approach is pretty straightforward, the problem in hand is divided into smaller subproblems and then each problem is solved independently. As we keep dividing the subproblems into even smaller problems, we eventually reach a stage where no more division is possible. These "atomic" smallest possible problems are then solved. The solution of all "atomic" problem sets are finally merged in order to obtain the solution of an original problem.

In the session this week ,we will discuss:

• The strategy of divide and conquer techniques
• Advantages of divide and conquer techniques
• Disadvantages of divide and conquer techniques
• The master theorem of divide and conquer techniques
• Applications of divide and conquer techniques
• Find the median of two sorted arrays

• Backtracking- 
  • Brute force approach
  • N queens problem
• After backtracking, we will be studying how Java 8 collections framework is implemented. We will be covering the following,
  • Set
  • List
  • Queue
  • PriorityQueue
  • Map
  • HashSet
  • TreeSet
  • ArrayList
  • LinkedList
  • Vector
  • Dictionary
  • Stack

Dynamic Programming is also an algorithmic technique for solving the optimization of problems. It is done by breaking the problem down into simpler subproblems and utilizing the fact that the optimal solution to the overall problem depends upon the optimal solution to its subproblems.

During this session, we will be covering the following:

• Dynamic programming- 
  • The strategy of dynamic programming
  • Properties of dynamic programming
  • Approaches of dynamic programming
  • 0/1 knapsack
  • Travelling salesman problem
  • Floyd Warshall

• In the end, we will conclude and summarize the course by having a brief discussion on Greedy vs Divide & Conquer vs Dynamic Programming.

An Entity–relationship model describes the structure of a database with the help of a diagram, which is known as Entity Relationship Diagram (ER Diagram). An entity relationship diagram (ERD) shows the relationships of entity sets stored in a database. An Entity may be an object with a physical existence – a person, car, house, or employee. Or, it may be an object with a conceptual existence like– a company or job. These entities can have attributes that define its properties. By defining the entities, their attributes, and showing the relationships between them, an ER diagram illustrates the logical structure of databases. ER diagrams are used to sketch out the design of a database. In this week we will be looking at-

• Entities, Relationships and Attributes
• ER Model and Relational Model
• Advantages and Disadvantages
• Attributes of relationships
• Simple vs Composite Attributes
• Single valued vs Multi-valued Attributes
• Stored vs Derived Attributes
• Complex Attributes
• Degree of a relationship and Cardinality Ratio
• Total vs Partial Participation
• Intention vs Extension
• Recursive Relationship
• How Relational Model is derived from Discrete Math

Once we have data, it is vital that it gets categorised into a database table. This allows for easy retrieval, editing, insertion and deletion of new or old data. This week, we will be looking at how to  create a database table. In specific we will be looking at

• Converting ER diagram to Tables in RDBMS
• Super Key vs Key vs Candidate Key vs Primary Key
• Integrity rules
• Entity Integrity Constraints
• Referential Integrity Constraints
• Constraints violated by Insertion, Deletion, Updation and Selection
• Steps taken by DBMS in case of constraint violation
• Authorization in relational databases
• Generalisation and Specialisation
• Aggregation

Database design is the procedure of organizing data according to a database model. The designer will determine what data must be stored and how the data elements interrelate. With this information, they can begin to fit the data to the database model. Database management system manages the data accordingly.

• Functional dependencies
• Relational Decomposition
• Multivalued Dependency
• Join Dependency
• Inclusion Dependence
• Normal forms-
• 1st Normal Form
• 2nd Normal Form
• 3rd Normal Form
• Boyce Codd Normal Form
• Codd’s rules
• Data-modeling with Unified Modeling Language (UML)

Structured Query Language or SQL is a standard Database language used to create, maintain and retrieve the data from relational databases like MySQL, Oracle, SQL Server, PostGre. As the name suggests, it is used when we have structured data. All databases that are not relational and therefore do not use SQL, are called NoSQL databases. we’ll be looking into NoSQL later in the course. In this week, we will be looking into-

• Declarative programming
• Studying SQL using MySQL and PhpMyAdmin.
• Characteristics of SQL
• Advantages of SQL
• SQl Data Types
• SQL Commands
• SQL Operators
• SQL Table queries
• SQL SELECT Statement
• SQL INSERT Statement
• SQL UPDATE Statement
• SQL DELETE Statement
• SQL Clauses
• SQL Aggregate Functions
• SQL Set Operations
• Dealing with NULL values

This week is a continuation of the previous one. Here, we continue to look into more topics related to the Structured Query Language.

• SQL JOINs
• Cartesian product
• Natural Joins
• Inner joins
• Outer Joins
• SQL Views
• SQL Sub Queries
• SQL Compound Queries
• Query Processing
• Materialization, Pipelining 
• Estimating Query Cost
• Query optimizations

• A NoSQL originally referring to non SQL or non relational is a database that provides a mechanism for storage and retrieval of data. This data is modeled in means other than the tabular relations used in relational databases. NoSQL databases are used in real-time web applications and big data and their use is increasing over time. NoSQL systems are also sometimes called Not only SQL to emphasize the fact that they may support SQL-like query languages. In this week we will having a -

  • Introduction to NoSQL
  • Document, Graph, Object Oriented, Hierarchical databases
  • Advantages and Disadvantages
  • MongoDB
  • Comparison with RDBMS
  • Relational vs document oriented
  • Your first MongoDB database
  • Querying in MongoDB- CRUD

MongoDB is the most popular NoSQL database. It is an open-source document-oriented database. The term ‘NoSQL’ means ‘non-relational’. It means that MongoDB isn’t based on the table-like relational database structure but provides an altogether different mechanism for storage and retrieval of data. This week we will be looking into the usage and applications of MongoDB. In specific we will be looking int-

• Creating and Retrieving products for ecommerce website
• Sorting and Pagination in ecommerce website
• Embedding vs Referencing in documents
• Data modeling in NoSQL
• Aggregation Pipelines
• Map Reduce

Redis is an open source (BSD licensed), in-memory data structure store, used as a database, cache and message broker. But before we proceed any further, we need to know what an In memory database is. An in-memory database is a type of purpose-built database that primarily relies on server memory for data storage, in contrast to databases that store data on disk or SSDs. In-memory databases are designed to attain minimal response time by eliminating the need to access disks. Because all data is stored and managed exclusively in main memory, it is at risk of being lost upon a process or server failure. These databases are ideal for applications that require microsecond response times and can have large spikes in traffic coming at any time such as gaming leaderboards, session stores, and real-time analytics. In this week we will be looking into-

• Why use In Memory Database
• Redis vs MongoDB
• The Pub-Sub model
• Install and use Redis
• Redis commands
• Backup
• Pipelining
• Security

PL/SQL is a block structured language that enables developers to combine the power of SQL with procedural statements.All the statements of a block are passed to oracle engine all at once which increases processing speed and decreases traffic. It was developed by Oracle Corporation in the early 90's to enhance the capabilities of SQL. PL/SQL is one of three key programming languages embedded in the Oracle Database, along with SQL itself and Java. This week, we will be focussing on -

• When to use Procedural Language?
• Functions
• Stored Procedures
• Triggers
• Notify customers as soon as the product is back in stock
• Common table expressions
• Recursion
• Cursors

Database scaling is a very vital process in running any database server. Essentially, as a website or application grows in size, the volume increases. For example, assume you have 10000 visits to a certain website. As the popularity of the website grows, the number of visitors starts to increase rapidly. Things have been working fine till this point but now you start observing the spike in the incoming traffic and you are not able to reduce the latencies and database failures even after adding plenty of memory and high-performance flash storage. You see, your Database server was designed to manage a small number of visitors to your website, as the number of visitors increase, your database infrastructure should also ramp up accordingly. This is done by database scaling. This week, we will be looking into-

• Storage system
• File structure
• B Trees and B+ trees
• Ordered vs Unordered File Organization
• Database Hashing
• Database indexing
• Database Keys and Indexes
• SQL Index
• Scalability and Indexing in key value database
• Database Partitioning
• Partitioning in redis
• Database Sharding
• Map Reduce
• RAID
• Data warehouse processing

This week we will be looking into how a database handles purchase orders, currency control and transactions. In specific, we will be looking into

• Transactions
• Diving deep into ACID
• Concurrency Control
• Need for Concurrent Execution of Transactions
• Inconsistency Problem due to Concurrent Execution
• Lost Update Problem
• Dirty Read Problem
• Unrepeatable Read Problem
• Phantom Read Problem
• Handling Deadlocks
• Data Backup
• Data Recovery
• Data Replication
• Security

• The role of a Servlet within a Java Application Server
• Reading an HTTP request and generating a response
• Get vs Post
• Introduction to Model View Controller in a Java web application
• Java Server Pages- using directives, handling errors
• Jakarta Standard Tag Library (JSTL)
• Java Beans
• Session management and tracking
• Event listeners, Event handlers
• Filters
• Asynchronous programming

• The Java Naming and Directory Interface (JNDI)
• JDBC (Java Database Connectivity)
• Connect with the MySQL database
• Mappings between Java objects and SQL tables
• Connecting an application with a data store using these mappings
• Similarities between Java data types and SQL data types
• Adding the Data Access Object (DAO) classes
• Initialize Data Sources with SQL scripts
• Execute SQL queries with JDBC Template and automatically map the results to your Data Objects
• Create a database and table using Java
• Create an entry in the database
• Update the entry in the database
• Read from the database
• Delete from the database
• Working against SQL injections

• What is a framework?
• What is the need for a framework?
• Identify the role of Spring as a Servlet application tool
• Architecture and project setup
• Spring configuration and Dependency injection
• Spring scopes
• Autowiring
• Spring Bean, Bean lifecycle
• Spring MVC
  • Request Response Lifecycle
  • Creating a Spring MVC Application
  • Application layers
  • Spring Components
  • Creating Controllers in Spring MVC
  • Populating the data model for a given view using the Controller
  • Using Thymeleaf in Spring MVC views
  • Springform
• Database connectivity

• How to use ORM to reduce development time and programmer error
• Understanding key concepts in ORM- Persistence Context and Entity Manager
• Hibernate
• Spring Data Java Persistence API (JPA)
• The JPQL (Java Persistence Query Language)- Writing and executing object queries in Java
• Isolating Entity scope through the use of annotations and Data Transfer Objects
• Propagating retrievals and persistence using Lazy Loading and Cascading
• Controlling the execution of queries through Transactions
• Customizing Spring Data Source construction and injection
• SQL vs Hibernate, combining both in the same project

The software industry is ever growing. One such industry which has gained massive pace is the online streaming industry. One such software used in video streaming is Kafka. Apache Kafka is an open-source stream-processing software. In this week we will talk about

• Kafka
• Kafka with Spring Boot
• Redis
• Redis with Spring Boot
• The Java Message Service (JMS) API 

• Connection with MongoDB
• Mappings between Java objects and MongoDB documents
• Similarities between Java data types and MongoDB data types
• Adding the Data Access Object (DAO) classes
• Create a database and collections using Java
• Create a document in the database
• Update the document in the database
• Read from the database
• Delete in the database

This is the final week of the course. Here you will be implementing further features of the eCommerce website. You will also learn to understand the existing application and refactor code

• Scatter and gather: The scatter and gather pattern is a tree pattern with a root that distributes requests and leaves that process those requests. Here, the requests are simultaneously farmed out to all of the replicas in the system. Each replica does a small amount of processing and then returns a fraction of the result to the root. The root server then combines the various partial results together to form a single complete response to the request and then sends this request back out to the client.

• Map Reduce: The model is used to target batch jobs where disk I/O is the major bottleneck. It uses a distributed file system so that disk I/O can be done in parallel. This pattern is used in many of Google's internal applications, as well as implemented in open source Hadoop parallel processing framework. I also find this pattern can be used in many many application design scenarios

• Bulk Synchronous parallel: This model is based on lock-step execution across all workers. It is coordinated by a master. Each worker repeats the following steps until the exit condition is reached, when there are no more active workers.
  • Each worker read data from input queue
  • Each worker perform local processing based on the read data
  • Each worker push local result along its direct connection

• Execution Orchestrator: This model is based on an intelligent scheduler / orchestrator to schedule ready-to-run tasks (based on a dependency graph) across clusters of workers.

• Shared-nothing architecture: A shared-nothing architecture (SN) is a distributed-computing architecture in which each update request is satisfied by a single node. The intent is to eliminate contention among nodes. Nodes do not share  memory or storage. One alternative architecture is shared everything, in which requests are satisfied by arbitrary combinations of nodes. This may introduce contention, as multiple nodes may seek to update the same data at the same time.
• Database Sharding: A shard is a data store in its own right (it can contain the data for many entities of different types), running on a server acting as a storage node. You can scale the system out by adding further shards running on additional storage nodes. The biggest advantage of this method is that you can scale the system out by adding further shards running on additional storage nodes. A system can use off-the-shelf hardware rather than specialized and expensive computers for each storage node. You can reduce contention and improve performance by balancing the workload across shards. In the cloud, shards can be located physically close to the users that'll access the data.
• Master-Slave Database: Master-slave replication enables data from one database server (the master) to be replicated to one or more other database servers (the slaves). The master logs the updates, which then ripple through to the slaves. The slave outputs a message stating that it has received the update successfully, thus allowing the sending of subsequent updates.
• Optimistic locking: Optimistic locking is a way to manage concurrency in multi-user scenarios. It is used to avoid situations when one user overrides changes made by another user without even looking at them. Locking - optimistic locking in particular - is a way to do that.
  
• Eventual consistency: Eventual consistency is a consistency model used in distributed computing to achieve high availability that informally guarantees that, if no new updates are made to a given data item, eventually all accesses to that item will return the last updated value.
  
• Pooling and multiplexing: Pooling and Multiplexing is a software creational design pattern that uses a set of initialized objects kept ready to use – a "pool" – rather than allocating and destroying them on demand. A client of the pool will request an object from the pool and perform operations on the returned object. 
  

• The pub-sub pattern-  The Publisher/Subscriber pattern, or “PubSub” for short, is a pattern that allows us to create modules that can communicate with each other without depending directly on each other. It’s a great pattern for decoupling our application and is quite common in JavaScript.
• Saga pattern- Saga pattern is a design pattern to handle system failures in long lived transaction by dividing the long lived transaction into a set of independent sub-transactions with compensating sub-transactions.
  

Relational databases store and provide access to data points that are related to one another. Relational databases are vertically Scalable. When the load increases on the database then we scale the database by increasing server hardware power. In this week we will look into

• Methods to scale a system
• patterns to scale a system

Summary of the entire courses with mentions of areas to focus