For an instructor lead, in-depth look at learning SQL click below.
Whether you are a budding data analyst, a seasoned IT professional, or just someone interested in database management, SQL or Structured Query Language is an essential skill to learn. This post aims to pave your path to understanding this powerful tool through simple and comprehensible examples.
What is SQL?
SQL, an abbreviation for Structured Query Language, is a computer language used to communicate and manipulate databases. Unlike other programming languages that can be used for a wide variety of tasks, SQL is specially designed to handle database operations.
Basic SQL Commands: CREATE, SELECT, INSERT, UPDATE, DELETE
Create
As the name suggests, the CREATE command is used to create databases and tables. Here’s a basic example:
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CREATE DATABASE TestDB; CREATE TABLE TestTable (ID INT, Name NVARCHAR(50)); |
Select
The SELECT statement is used to select data from a database. The data returned is stored in a result table, called the result-set. For instance, if we want to select all the data from the TestTable table, we write:
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SELECT * FROM TestTable; |
Insert
The INSERT INTO statement is used to insert new records in a table:
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INSERT INTO TestTable (ID, Name) VALUES (1, 'Test'); |
Update
The UPDATE statement is used to modify the existing records in a table:
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UPDATE TestTable SET Name = 'Updated Test' WHERE ID = 1; |
Delete
The DELETE statement is used to delete existing records in a table:
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DELETE FROM TestTable WHERE ID = 1; |
Conclusion
Learning SQL can open new opportunities for you. It is the foundation for a career in data analysis and database management. While this post has touched upon the very basics of SQL, the language has much more to offer.