A quick review of Structured Query Language (SQL) - SQL Tutorial

- In this course, we'll focus on building fundamentals to get you started with using a database for a project. But, what is a database anyways? Well, a database is simply a collection of data arranged for retrieval of the data by a computer system. Let's say you're a business owner and you're selling a product. Most likely, you want to keep track of the amount of orders you receive. You may also want to know the dates of these orders, so that you can see trends or know how many orders you get each quarter. You should also keep track of your customers so that you can see what they like and what they don't like. A database is often organized as a collection of tables. A table is a two-dimensional grid consisting of rows and columns. A row is also known as an instance or a record. A row can be a student, a product, a customer, or an order. The column is also known as a field or an attribute, as it describes something about the row. In the case of a product, it could be the product's size, color, product name, or category. The most widely used language for managing data from a relational database is known as SQL. Structured Query Language, or SQL, or S-Q-L, is the primary language we use to manage and access structured data in a Relational Database Management System. It's how we communicate with the database. A Database Management System, or DBMS, is a software application that helps us store, load, and update data. We can also use the DBMS to retrieve data or query directly. In addition to the relational database model, there are different types of database models. Some of the models include the entity-relationship, or ER model, and object-oriented relationship models that we'll discuss later in another section. Time for a brief history review. The SQL language was first developed in the 1970s by IBM researchers Raymond Boyce and Donald Chamberlain based on the relational model developed by Edgar F. Codd in 1970. He wrote the paper, "A Relational Model of Data for Large Shared Data Banks," which provided a theoretical base for working with structured data. This research led to the first Commercial Relational Database Management Systems, Oracle in 1979, SQL/DS in 1981, and DB2 in 1983. As you can see, SQL is an old programming language, so why is it still relevant and why do I need to learn it? There's an easy answer to this. Many companies still use it. According to the 2020 Insights from Stack Overflow, SQL is the third most commonly used programming language behind JavaScript and HTML and CSS. Having a good database understanding is essential in today's job market. And it's not standing still. New concepts in database technology include processing big data. Big data is a concept of collecting, organizing, and analyzing massive amounts of data from a variety of sources. You may have heard of technologies, such as Hadoop MapReduce, NoSQL, and NewSQL. Big data concepts involve analyzing and extracting information from enormous data sets that will require multiple servers and lots of compute power to process. As application developers, we develop code that calls the Database Management System to perform operations or retrieve data from the database, and this course will help H Sport display their sales dashboards and give you essential SQL skills to put in your toolbox. Let's get started.