SQL

Question

I have completed the SQL course but I don’t really understand why to use it. Could you explain and tell if you have ever used it?

Answer 1

How applications works.
Imagine facebook, when you open facebook you see images, friends post, chat ...Everything you can see with your eyes is called FrontEnd. It is html, css, javascript. For example when you click somebody's profile FrontEnd makes Get request to certain endpoint. Endpoint looks like facebook.com/user/135. This request is handled by the server. Server is also called Backend. It can be writen in every language you like - c#, java, php.... After server handle request, it should give user with id 135. Server make SQL query in database which looks like SELECT * FROM USERS WHERE user.id=135. Server gets the info of that user and send it to the frontend, then frontend visualize it.
Now you can see whole picture. If you are backend or database developer you will need SQL.

Answer 2

SQL is really important if you work with data and databases.
As soon as you want to save some data in a database you need SQL.
If you want to retrieve data from a database you need SQL
Try to code a library app. Make a books-table. Read the rows from the database, Store new books in the database and give the user the possibility to update book-defintions.
In what did you make so far and in what language ?
I use it a lot. I use the sql-express as database and sql as querylanguage.

Answer 3

It can also be used in the context of statistical (machine) learning. When you have massive datasets and you'd like to work with a subset of the original dataset, SQL is the way to go.

Answer 4

Sql is a must for developers. If you need to create an application,obviously there must be a database. Even to hack something, you must get access to databases, then you must know sql commands to retrieve information. So Sql is important.

Answer 5

Daniyal mustafa please start a own thread. Your question is not a answer to this question.