For an instructor lead, in-depth look at learning SQL click below.
These days, having SQL skills is a necessity in many job roles. Whether you are a web developer, data analyst, or even a business manager, understanding how to manipulate and analyze data is crucial. If you’re new to SQL, this quick start guide is for you! I’ll guide you from the very basics to writing your first SQL query.
What is SQL?
SQL, or Structured Query Language, is a standard programming language specifically designed for managing data held in a relational database management system (RDBMS). With SQL, you can query, insert, update, and modify data. Essentially, it’s a powerful tool you can use to converse with databases and get them to spill their secrets!
The Basics
The first thing you need to know about SQL is its syntax and structure. Here is a very basic SQL statement:
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SELECT * FROM Employees; |
This query is saying “get everything from the Employees table”. The * symbol in SQL is a wildcard character that means “everything” or “all”.
The SELECT Statement
The SELECT statement is used to select data from a database.
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SELECT column1, column2 FROM table_name; |
This statement selects only the ‘column1’ and ‘column2’ data from the ‘table_name’.
The WHERE Clause
If we want to add conditions to our queries, we use the WHERE clause. The WHERE clause is used to filter records.
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SELECT column1, column2 FROM table_name WHERE condition; |
For instance, you can use this to get data of employees who have a salary greater than 50000.
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SELECT * FROM Employees WHERE Salary > 50000; |
Summary
This guide is just the tip of the iceberg of what SQL can do. SQL is a vast language with lots of functionalities that allow for complex database manipulation and data analysis. The best way to learn is by doing. Continue practicing SQL queries, and you’ll soon become proficient. Happy querying!