SQL stands for Structured Query Language. SQL is a standard language for storing, manipulating, and retrieving data in databases. According to ANSI (American National Standards Institute), it is the standard language for relational database management systems. SQL lets you read and change databases. SQL is a programming language but it is not a general-purpose language. SQL was designed to update, add, delete a row of data and retrieve subsets of information within the database. There is an acronym for this: CRUD. CRUD stands for Create, Read, Update and Delete.
SQL is a domain-specific language used in programming and designed for managing data held in a relational database management system (RDBMS). What is a RDBMS? A relational database is a (most commonly digital) database based on the relational model of data, as proposed by E. F. Codd in 1970. An RDBMS must do these two things:
- Present the data to the user as relations (a presentation in tabular form, i.e. as a collection of tables with each table consisting of a set of rows and columns)
- Provide relational operators to manipulate the data in tabular form.
Learning SQL
At this website we have a lot of posts about SQL. Many of those posts are part of a series of posts. We have a Category called SQL Server with dozens of posts. Under that category, some of the posts are part of a series. For a list of the SQL series go to the post called SQL Server Introduction.
For a good tutorial on SQL, have a look at w3schools.com‘s SQL Tutorial. They also have a SQL Keyword Reference.
Where Do I Start?
If you are new to SQL, start with the SELECT statement. Start with w3schools.com mentioned above. After you are comfortable with SELECT, have a look at the logical processing of the SELECT statement at the post called SQL Server Logical Query. Don’t worry if you don’t fully understand that post. You can come back to it later. Also, have a look at the post SQL Best Practices.
Learn with YouTube
Alex the Analyst has a video on SQL for beginners and intermediate level folks called SQL Beginner to Advanced in One Hour | CareerFoundry Webinar. It’s one hour and eight minutes long. It’s a quickly paced tutorial created in the summer of 2023.