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Mateusz Jasiński
Mateusz Jasiński

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PHP 0 to hero pt.9 - setting up SQL (SQL pt. 1)

#webdev #beginners #sql #tutorial

What's up - welcome in another part of this course

Today, we start very important topic - using databases in PHP

This part is an introduction - there will be 2 other parts about strictly coding

So, what do we do today?

We will

  1. Learn something about PHPMyAdmin and MySQL
  2. Create our first database
  3. Familiarize ourselves with terms like primary key, row, column, SQL, DBMS
  4. Data types in SQL-based databases

So, let's get started

What will we use today

This time, we will utilize another software - DBMS

What is it? It stands for Database Management System
There, my choice is MySQL - we have it installed with XAMPP
(To be fair, it's MariaDB)

But remember - that's not the only one

We have plenty of those. There are differences in writing SQL code then - also PHP syntax might be different

Some of the most popular are

Another thing is software - We have utility built in XAMPP (and installed in linux) called phpmyadmin

This allows us to work with database graphically, rather than via queries

And, what is a query? That's a structure, that tells database to perform some action - like select some data or update them

We write them in language called SQL - structured query language

Let's see what it really looks like

Launching PHPMyAdmin

First thing - enable MySQL service in XAMPP (Or start mysql-server and mysql-client in linux)

Then, when this and Apache is working - we can access phpmyadmin

Go to http://localhost/phpmyadmin

At first - it looks like this

First glance

(Here I've got some databases from my previous projects - you should have it empty)

We'll familiarize ourselves with some of these - right now click new inside sidenav - you should be redirected to page like this

Creating database

Creating database

Let's create a database called firstProject - choose whichever encoding suites your language from ones starting with utf8 and ending with ci

As I am polish, I've chosen utf8_polish_ci

After inputting everything - it looks like this

Ready to create database

Now, next page

Table creation view

Database designing

We will create simple to-do app - so we need 2 tables

  1. users - It will have 3 rows (right now)

    • user_id - Numerical user id (It will be our primary key)
    • username - self-explanatory
    • password - user's password - I think also self explanatory

  2. tasks - All tasks will be stored here. It will consist of 5 rows

    • task_id - Primary key for this table
    • task_title - self-explanatory
    • description - description for user about specific task
    • creator - Task owner. It will be user_id of whoever created this task
    • timestamp - when was task created

What's a primary key?

Primary key - It's a column in the table (most of the time numerical), that's unique to all records (rows) - like here id.
It is used to distinguish rows in table

Creating tables

First, let's create users

Add name and number of columns - here 3

What should it look like

Then we end up here

Table creation page

Let's start with Name

After inputting names that we agreed to, we should have something like this
View right now

Next part - type

This indicates what type of data will be stored there

We have a bunch of them, like DECIMAL, BOOLEAN

So, what types will we have?
user_id - will be INT
username - will be TEXT
password - as well TEXT

Named columns with types

Now, we have this - one last thing

We were talking about primary key - have we specified it? No

So, let's do it

There is a column called index - in row with user_id click on it, and choose PRIMARY

On pop-up - just click go and don't bother

Right beside it - we have suspicious checkbox labeled as A_I

Is it to fill it with data generated by AI? Not really

A_I stands for AUTO INCREMENT - we know the verb "to increment"

So, this option means that when we pass an empty value here (NULL) it will automatically replace it with incremented value of previous row

So, if we added a new row here it would automatically set user_id value to 1

If we added next row, it would fill it with 2. And so on

If you hadn't realized it yet - we have to check it

After all - it looks like this

Ready table structure

Click Save button below and boom - we should be redirected to page called structure

Table structure

Looks like it's fine - let's create the second one

Click New in database drop-down menu on navbar

Where to click

Up here

place for table name

Add table name. We have only 4 colums, but we need 5

Click Go button beside table name - it will add a new column

Now - fill it

Filled table

As you see, I allowed myself to skip explaining everything - you should know, how it works and what some of those mean

One thing I want to tell you about is DATETIME type

It allows us to store dates in standardized MySQL format - YYYY-MM-DD hh:mm:ss

Here, those letters stand for one digit of
Y - year
M - month
D - day
h - hour
m - minute
s - second

Click Save and job is done

We have successfully created a database in PHPMyAdmin

Conclusion

As you see, today we have written no code - but don't worry.
Next parts will have more of coding

Check out other parts of this series - wait for next ones and see you in next articles

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