Introduction¶
SQL (Structured Query Language) is a very powerful tool in the modern age, and has been for many years. It is a rather simple language designed for interacting with most modern day database infrastructure, and has even gone as far as being declared by ANSI as the national standard for all relational database management systems.
Like Python, SQL is a high level "language" that uses a human readable format for its syntax structure, and as such, it is a relatively easy language to learn.
Example SQL query¶
To better understand the above query, below is an example table to visually explain what the query is requesting.
table_1
| id | column_1 | column_2 |
|---|---|---|
| 1 | Hello | False |
| 2 | World! | True |
With the example query above, the output would be World!, this is because when the query is run it SELECTs all the values of column_1 FROM the table named table_1 WHERE the value of column_2 is equivalent to True. Since the value of column_1 is World! on the same row that the value of column_2 is True, then that is the value that we are looking for with the example query.
Where do I begin?¶
Starting with SQL is relatively easy, there are many means of setting up local SQL databases that you can freely play around with, and there is also many resources to help get you up and running with SQL in no time. It seems to be the case for many that simply making an example database and trying to manipulate the data within, or trying to get data out via queries is one of the best ways to learn SQL, but along with this there are multiple resources below for learning SQL.
Text resources¶
| Name | Description | URL |
|---|---|---|
| W3Schools.com | Easily one of the best free and interactive SQL tutorials. If you've been programming for some time now, there is a very good chance you have come across if not used some of W3Schools' resources before. Overall a very useful and in-depth course that covers everything that you will need to know regarding SQL. | www.w3schools.com/sql |
| Codecademy.com | Like W3Schools, also an incredible resource for learning anything and everything SQL. A more traditional "course" than that of W3Schools' offering, that uses a project based approach to learning instead of little incremental chunks. The course will teach you how to make and work with your own databases, and create meaningful queries for the tables/data within. | codecademy.com/learn/learn-sql |