What is Database - simplest lesson on earth
This is the simplest database lesson on all universe.
Think this story:
You are a working man, Your name is P.H.P. Then Imagine the database just like librarian boy, working on other room. His main work is writing notebooks. erasing and changing pages. but there is little problem; He is talking foreign language which is called SQL, so how do you communicate with him.
Guess what: You need to learn SQL language. If you know this language then you can give orders to him.
orders like this:
- Give me the book called "lessons"
- Hey boy, please delete page eight on "lessons" book
- Erase all pages about John Smith
And this senario changes when some other worker comes from window, His name is ASP.NET. he wants to change some page. Then he just need to give orders with SQL language.
in this picture, there can be another working people from this window. Like; C++(we call him big C.), Python(Guess why we call him snake) , ASP (Little brother of ASP.NET).
You can learn SQL language: its too easy. because there is only 4 main predicate words in this language.
- SELECT (give)
- DELETE (erase)
- UPDATE (change)
- INSERT (write)
You can work in this job if you learn this words. is it look very hard ?
no I will teach you this words. Then you can talk with librarian boy.
Here is some example sentences and their meanings on SQL language.
DELETE FROM `lessons`
means: erase everything from lessons `notebook`
SELECT `name` FROM `users`
means: give me names from notebook named `users`
If this examples is too hard for you, please write about it below. I will be waiting for help you.