Learn to communicate with databases using SQL, the standard data management language. Obviously, a quick tutorial is not to make anyone an overnight expert, but as far as SQL Server For Beginners expanding upon the Scott schema or the newer sample schemas (HR, OE, SH, etc.) goes, the sample schema in SQL Developer provides a good reference structure or setup. SQLfiddle is the perfect tool to test queries, compare and contrast SQL statements in different database back-ends, or when you don't have a particular database platform readily available but would like to see what a given query would look like in that environment.
Apps like Instagram and Snapchat use SQL to store a user's profile information such as bio and location, to update the app's database when a user creates a new post or shares a photo, and to record messages sent from one user to another so the user can retrieve the messages to read again at a later time. However, some features of the SQL standard are implemented differently in different database systems. If you're still using SQL Server 2008, this is the tutorial for you. SQL developer is a free database management and development tool created by Oracle itself.
The course uses both Microsoft SQL Server and PostgreSQL, and the best part of the course is that its focus is on enhancing your data analytics skills with real-world data science exercises. It does use plenty of SQL syntax but the real goal of this book is to familiarize the reader with general database theory. Oracle is the leading SQL database system in the world. Start with the short introduction to the syntax of SQL because you will use it to interact with tables. This website provides users with a set of tutorials on managing MySQL databases and manipulate data.
A primary key is a special column within a SQL table that is used to identify records uniquely. The major benefits of using a foreign key in SQL is Data Integrity, and it avoids notifications that could violate the data integrity rules. First, you will learn how to query data from a single table using basic data selection techniques such as selecting columns, sorting result set, and filtering rows.