For an instructor lead, in-depth look at learning SQL click below.
Welcome to our SQL crash course, designed to kickstart your knowledge about one of the most popular and useful programming languages. Structured Query Language, SQL, is an industry-standard language designed to communicate with databases. It’s used by many businesses to handle all sorts of data needs. Whether you’re trying to master databases for your career or you need to manage data in your own projects, SQL is the language you need to know.
Understanding SQL
SQL is a language that helps you access, manipulate, and define databases. It allows you shape and instruct databases giving commands on what you want either retrieved, updated, or deleted. SQL ran the gamut of abilities from performing calculations on data, transforming a dataset, aggregation of data, and more.
Reading Data with SQL
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-- SQL code to retrieve all data from a table named Employees SELECT * FROM Employees; |
This will return a table that includes all the rows and columns of the ‘Employees’ table. The asterisk (*) is a wildcard character that represents ‘all’.
Filtering Data with SQL
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-- SQL code to retrieve specific data from a table SELECT * FROM Employees WHERE Salary > 50000; |
This will return rows from the ‘Employees’ table where the ‘Salary’ is greater than 50000
Updating Data with SQL
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-- SQL code to update data in a table UPDATE Employees SET Salary = 60000 WHERE EmployeeID = 1; |
This would update the ‘Salary’ of the employee with the ‘EmployeeID’ of 1 to 60000.
Conclusion
SQL is but a simple yet powerful tool that every data professional should understand. The possibilities with SQL are endless and the command over data it provides is invaluable. With practice and experience, you will be able to breeze through databases, big or small, with a few simple queries!