Try   HackMD

Database Management for Beginners

IMG_256

Source

What is a Database?

A database is simply a collection of data or records, which is organized in a manner that we can perform operations on it. These records are stored in the form of tables with rows and columns. Rows are known as tuples and columns are known as attributes of the database.

A database stores its metadata in a data dictionary. Metadata is any information about the data, like its schema, constraints, structure, etc.

What is a Database Management System?

Database management is basically the management of different types of data, such as textual data, numerical data, and binary data with the use of database management systems.

A database management system or DBMS is a software used to manage a database (stored data). Some well-known DBMSs are MySQL, PostgreSQL, etc. A DBMS provides us a platform to interact with data, store it, and use it.

Let's see some popular DBMSs in detail.

MySQL

The first popular database we will discuss is MySQL. So, what is MySQL? It is an open source relational database management system (RDBMS) that organizes data into data tables, which helps in structuring the data.

It uses SQL, which is a language, used to create, modify, and extract data from databases. MySQL is developed by Oracle Corporation.

MySQL is used by big MNCs like Youtube, Facebook, Paypal, Netflix, Uber, and many more.

PostgreSQL

The next database we will turn to is PostgreSQL. And, what is PostgreSQL? It is a free, open-source relational database management system (RDBMS). It's an enterprise-class database that provides extensibility and is compatible with SQL. It's also known as Postgres.

Postgres transacts with ACID properties (Atomicity, Consistency, Isolation, Durability). It supports both SQL (relational) and JSON (non-relational) querying. PostgreSQL is used by MNCs like Apple, Instagram, Spotify, NASA, etc.

MongoDB

And not the final DB you should know about: What is MongoDB? It is a document database which provides scaling and helps in the development process as it has the same structure as some programming languages. In MongoDB, a record is composed of key(field) and value pairs.

MongoDB has many unique features–-replication, indexing, load-balancing, server-side Java execution, etc. It can be used as a file system and provides serverless accessibility.

MongoDB is also available as an on-demand fully managed service. MongoDB Atlas runs on AWS, Microsoft Azure, and Google Cloud Platform. Big companies like Forbes, Google, Toyota, KPMG, and many more use MongoDB.

What are the Types of DBMS?

Hierarchical DBMS

A hierarchical DBMS organizes data in a tree-like structure, either in a top-down or bottom-up design. It's defined by a parent-child relationship.

There are two types of relationships:

  • one-to-one: A parent has a single child.
  • one-to-many: A parent has multiple children.

One child can't have multiple parents.

IMG_256

Source

Network DBMS

A Network DBMS is an extension of a hierarchical DBMS in which data can have many-to-many relationships and appears in the form of a network. In this database structure, a child can have multiple parents. Therefore, it allows you to model more intricate relationships.

IMG_256

Source

Relational DBMS

A relational DBMS uses a logical relationship of entities to create a database. It's one of the most extensively used arrangements for organizing databases. It organizes and stores data in independent tables and allows them to relate and connect with one another.

The data stored in this is structured and can be accessed/modified by SQL.

IMG_256

Source

Object-Oriented DBMS

An object-oriented DBMS describes data as an object that stores values and operations. Objects with similar features are grouped as a class. This is compatible with many OOPS languages, like C++, Python, Java, Scala, etc.

IMG_256

Source

NoSQL DBMS

A NoSQL DBMS is used to store a wide range of data sets. It's not a relational database. We can further divide it into four types:

  1. Key-value storage: Every item is stored in the key-value format.
  2. Document-oriented storage: It stores data in JSON-like documents. It stores data in the same format as used in the application code.
  3. Graph database: It stores vast amounts of data in a graph-like structure.
  4. Wide-column stores: Data is stored in large columns together, instead of storing in rows.

What are Database Languages?

Database languages are used to read, store, and update data in the database. These are used to express database queries and updates.

  1. Data Definition Language (DDL): It's used to define a database's structure and patterns. You can create the skeleton of the database. It's used to store the metadata in a database, like schemas, constraints, etc.
  2. Data Manipulation Language (DML): It's used for accessing and manipulating data in databases. It handles user requests, like SELECT, INSERT, UPDATE, etc.
  3. Data Control Language (DCL): It's used to retrieve stored data. Its execution is transactional. It includes tasks like GRANT, REVOKE, etc.
  4. Transaction Control Language (TCL): It's used to run the changes made by the DML. It can be grouped into logical transactions. This includes tasks like COMMIT, ROLLBACK, etc.

Why Do We Need DBMS?

DBMSs provide the following advantages:

  • Data sharing: With a DBMS, it's easy to share data using the correct authorization protocol. Multiple users can access and work on data concurrently.
  • Data integration: They store all data in one database file, which removes redundancy and improves integration of data.
  • Efficient and safe: It saves time in maintenance and operations. Also, due to their in-built authorization protocols, the data is safer. DBMSs provide better confidentiality and safety guidelines. It reduces a lot of external efforts from users.
  • Backups and Better view of data: A DBMS provides well-managed and structured data, on which operations are easy to perform and observations and decisions can be made more effectively. It also provides backup subsystems, which help when there is some problem or crash. It restores your data if required.

Conclusion

Data is the future. In times like these where everything is online, there is a ton of data generated on a daily basis. All this tells us that data is very important. With different types of large, unstructured data, there is a need to manage that and use that in a way that would be helpful for all. There are many roles and streams developing for this duty like Data Engineer or Data Scientist, but it all starts with a Database Management System.

Last changed by 
 
Sam Frankson
0
1050

Read more

How to Ensure Runtime Protection for Application Security

Software applications are at the core of the whole digital world. Hence, application security plays an essential part in the software development process, as hackers always come up with new and different ways of getting access to the system, therefore, application security is always the highest priority in most organizations. Application security is the process of using best practices and techniques to secure the software and hardware of the computer systems from any outside malicious attacks. In simple terms application security can be described as using different security measures at the application level for preventing unauthorized access and the leak of valuable information or data from the software application. Even after employing various security techniques some of the vulnerabilities go unnoticed during the quality assurance phase and they end up in production, which hackers can use to their advantage to get unauthorized access into the system and cause a security breach. Once a vulnerability or bug goes into production, even the network defenders find it difficult to defend the applications from various attacks. This can be protected by ensuring that the applications themselves identify the attacks and protect themselves in real-time. Such protection can be ensured using runtime protection. So, this article explains what is runtime protection and how it can be used to secure the application in production. Runtime Protection The application layer of any software application is the most attacked layer and is considered to be the difficult layer to defend in the entire software stack, hence it requires various appsec testing tools to ensure that the application runs securely while it is deployed to production. These tools are mainly divided into two main categories of security scanning and runtime protection tools. Security scanning tools are used when the applications are in the development stage to detect and remediate the security vulnerabilities and risks while runtime protection tools are used while the application is in production and it works as an extra layer of security to the application.

Oct 31, 2022
Best Practices for Data Ingestion

Many of the enterprise's mission-critical engines, including business intelligence, predictive analytics, data science, and machine learning, are powered by data. Like any fuel, data must be plentiful, accessible, and clean in order to be completely useful. The stages of extract (taking the data from its current place), transform (cleaning and normalizing the data), and load are typically included in the data ingestion process, which prepares data for analysis (placing the data in a database where it can be analyzed). Extract and load are normally simple for businesses, but transform is often a challenge. As a result, if no data has been ingested for processing, an analytical engine may lie idle. What is Data Ingestion? Data ingestion is described as the procedure of gathering data from several sources and sending it to a destination where it may be deposited and examined. The destination can generally be a database, data warehouse, document storage system, or data mart. However, there are a variety of sources available, including spreadsheets, web data extractions (also known as web scrapings), internal programmes, and SaaS data. Source Business data is frequently stored in several sources and formats. For instance, Salesforce.com keeps sales data whereas relational DBMSs store product information. Since this data comes from many sources, it needs to be cleaned and transformed into a format that can be easily examined for decision-making using a simple data intake tool. If this is not done, you'll be stuck with pieces that can't be stitched together.

Oct 17, 2022
What is Load Testing and Why Should You Implement It

Photo by Sigmund on Unsplash As a software development project nears completion, it has almost definitely been subjected to a number of tests, particularly in extreme testing environments where testing and development occur concurrently. There's only one way to tell if your software can withstand the pressures that your end customers will soon put on it: load testing. What is Load Testing? Load testing is one of the several methods of performance testing. Load testing is used to verify a system's performance under real-world settings. Load testing is a software testing procedure that assesses the performance of a software application under a certain expected load. JMeter Load Testing is a testing technique that uses Apache JMeter, a Java-based open source desktop software. It determines if the web application under test can handle high demand. It also helps in examining the entire server under high demand. Load testing is used to improve performance and verify the stability and seamless operation of software applications prior to deployment. How it Works

Aug 12, 2022
Conducting Parallel Testing in Regression

Photo by David Travis on Unsplash Today, there are many types of testing methods in the software development lifecycle, each having advantages and disadvantages in terms of efficiency, time-saving, cost, reliability, usability and so on. In general, we can categorize software testing methods under four main headings: functional testing, non-functional testing, manual testing and automated testing. In this article, we will focus on what automated testing is, why it is useful, main techniques in automated testing like regression testing, and some popular tools for automated testing. What Is Automated Testing? In general terms, automated testing is testing software or programs utilizing some automation tools for many edge cases instead of a human-driven manual process of monitoring and validating a product. In the market, there are some popular tools that offer a wide range of services for automation testing like Selenium, WebDriver, Appium, and Cucumber. Source

Mar 22, 2022
Read more from Sam Frankson
Published on HackMD