SQL Tutorial: Introduction to SQL Server

Want to learn more? Take the full course at https://learn.datacamp.com/courses/introduction-to-sql-serverat your own pace. More than a video, you'll learn hands-on coding & quickly apply skills to your daily work. --- Welcome to the course! Most of the world's data live in databases, so learning how to access and extract insights from these data is an essential skill for any data scientist. SQL, or S-Q-L, stands for Structured Query Language, and is the native language for working with databases. SQL Server is a popular relational database system developed by Microsoft. Transact-SQL, or T-SQL, is Microsoft's implementation of SQL, with additional functionality. In this course, you will master the fundamentals of T-SQL and become prepared to work with SQL Server databases. You'll do this by writing queries, or statements. Let's get started! Think of going to the supermarket - we have a store full of goods - that's our database. We want to fill our cart with products, and those products are our query results. Unlike the supermarket, we can't physically retrieve our data and manipulate it, so we write queries to make this happen. The key term when retrieving data from tables is SELECT. SELECT statements specify what we want to retrieve from a table. The simplest query selects one column, from one table. In this query, we select the description column, from the table 'grid'. Note the semicolon which denotes the end of the query. The other keyword you will always need is FROM - to specify the location of the source table. Here are the results. By default, the query returns every row in the selected column. You can select multiple columns, separating each column name with a comma. However,you don't need a comma for the final column selected before 'FROM'. Here are 2 similar queries, with different layouts. The top query shows all the columns to be selected in one line. The bottom query shows each selected column on a new line. The results