PHP programming basics for beginners. Bootstrap framework: fast adaptive layout


There are disciplines in web programming that any person associated with the World Wide Web must know the basics of. Therefore, one way or another, you will have to learn PHP and MySQL. And if you don’t want to, then greed will still force you:

Why learn php and mysql?

This question can only be asked by those who are not at all familiar with the specifics of building a web space and its modern basis. Any person more or less knowledgeable in programming will say that these two disciplines are currently dominant in world wide web. This means that almost the entire Internet is built on PHP based and MySQL:


Although nowadays PHP value decreased a little. And all because of the large number of engines, which (ironically) are also built on the basis of this language.

In the modern web world, engines mean any content management system (CMS). Most of them are written in PHP and MySQL.

Each CMS is software basis, equipped user interface. Its tools greatly facilitate the process of site administration. But then why bother learning PHP from scratch? After all, you can simply go to the administrative part of the resource and perform all the manipulations using the tools built into it.

Let's start with the fact that not many people have the patience, time or energy to study PHP and MySQL. A person must come to this himself. But those who decide to comprehend these disciplines will receive:

  • A profession in demand - smart programmers have always been in great demand on the labor market. But even inexperienced beginners with good theoretical knowledge of PHP and little experience in web programming will be able to find a job with decent pay;
  • Remote work – in order to engage in programming, you don’t have to get up early, get to work and follow a dress code. All this can be left outside the door and create program code sitting at home in slippers;
  • Saving money - if you own a website, then of course you know that the services of professional web programmers are expensive. And for someone starting their own business on the Internet, every penny is valuable. Selfeducation MySQL and PHP will save money and put it in the right direction.

As already noted, most modern engines are based on PHP. Although their fault tolerance is at high level, but no one has canceled the influence of the human factor. Therefore, CMS code sometimes behaves differently than the web programmer intended.

And to correct this mistake, you need to look for a specialist and pay him a lot of money. And then it turns out that the whole problem was in just one line of code, which could be easily fixed even with knowledge only basic principles PHP.

  • An interesting hobby - web programming is not only a means of making money or saving it. This is also an exciting activity that combines both technical start, as well as the creative component.

Learning PHP and MySQL can be a means of self-expression for many.

What is PHP

PHP refers to scripting languages programming. It is most often used to create web applications and web services. This language is supported by most hosting sites on the Internet. The bulk of dynamic sites are written on its basis.

In a dynamic site, unlike a static one created only in html, the content of all pages is generated in response to a user request. The resource structure is formed based on template files, and the content is (most often) loaded from databases.


The popularity of PHP is due to its following characteristics:

  • Majority support popular DBMS (Database Management Systems);
  • Automatic sending of HTTP headers;
  • Built-in support for working with sessions and cookies;
  • Tools for working with deleted files;
  • XForms support ( XML-based forms);
  • Proximity PHP syntax to the C language;
  • Lack of strict typing - variable typing is done dynamically.

Data types are where you start learning PHP

  • OOP support ( object-oriented programming);
  • A large set of superglobal (predefined) arrays designed to work with the web space.

What is MySQL?

MySQL is a freely distributed DBMS from Oracle. Together with free version Commercial releases are also being developed to order. It is thanks to this that all new developments of the corporation are necessarily implemented in free releases of the DBMS:


Features of the MySQL DBMS:

  • Support for data replication mechanism starting from the first releases of MySQL.

Replication is the process of synchronously copying all changes to a source on several of its copies at once. That is, any action on the data of one copy of an object will be reflected in all its other samples.

  • Work with both local and remote sources is supported;
  • Built-in support for a large number of table types. And thanks to open source the list of supported table types is increasing;
  • Wide range of cross-platform functionality;
  • Database table size MySQL data limited only by possibilities operating system, on which the DBMS is deployed;
  • Support for most popular programming languages ​​via API ( application interface).

More detailed information You can learn about the capabilities of the DBMS from any tutorial or reference book on MySQL.

Where to begin?

From the bitter experience of many beginners, we can conclude that main problem self-study PHP and MySQL is the right choice software. And all due to the fact that PHP is a server-side programming language. Therefore, to test the code you need not only a special editor, but also a local server:


Several optimal options:

  • Apache HTTP Server – can be downloaded from the developer’s official website;
  • Denver is the most best option for installation and further use. The installation package includes an Apache server, PHP and MySQL. In the first option, you would have to download and install all this separately.


  • XAMPP is a suite that includes PHP and MySQL. And also a built-in PHP tutorial:


Both sets include a utility for creating and modifying databases on MySQL based using T-SQL queries. But to write code in PHP, you will need an editor that supports the syntax of this language. Some of the most suitable options:

  • PHPEdit ;
  • Microsoft WebMatrix;
  • Kantharos PHP IDE;
  • Adobe Dreamweaver.

From the author: Is it necessary to know the PHP programming language? If you are going to throw in your lot with website building, you will have to. Even if you really don’t want to! Why is that? We will try to answer all the common “whys” associated with this language in our material.

The solution that “holds” the Internet together

This is exactly how one of my acquaintances, who has been creating Internet resources for more than a decade, described PHP. And he’s right, probably 200% percent (or maybe more).

The history itself of this language suggests that he was born to “blind” the current version of the Network to which we are so accustomed. This is probably why some people still cannot realize its power, even after learning the basics of PHP programming.

Proving the role of PHP in creating the Internet is a thankless task. Here, as they say, supporters of others can begin to speak out server languages. They say that the “hypertext preprocessor” (as the abbreviation PHP stands for) has already outlived its usefulness. Many of its functions are implemented even in…

Well, shouting and waving your arms, extolling your programming language, which you specialize in, is a simple matter. But the best “evidence” indicating the demand for PHP is its prevalence.

The following rating of program languages, compiled by TIOBE specialists last summer, tells us that PHP already has been consistently ranked among the top for several years. You haven't started searching by programming language yet PHP tutorial? You'll be running soon.

If you are wondering why Java has jumped so much, then the answer is: thanks to the Android mobile operating system, applications for which are developed in this language.

Own rake

Back in the early 2000s, I was engaged in “research” in the field of programming. I kept trying to figure out which “party” of developers I should join, which discipline I should devote my life to studying.

In principle, I did not consider PHP as a programming language for beginners. He seemed too confused. Here's the other thing about ASP.NET: a commercial language based on C#. Oh, what castles in the air I built back then! And there were all the prerequisites for this:

The technology was developed by such a “thought giant” as Microsoft.

Availability of specialized software – powerful editor Visual Studio.

Extensive and well described documentation.

Hope for a “healthy” future.

ASP.NET, unlike PHP, was much easier for me. Visual Studio automated a large number of operations for writing server scripts. For example, thanks to the excellent visual editor it only took a few minutes to create a web page. By dragging and dropping controls and styling them in the editor, you could make a website in less than an hour!

But the PHP programming language from scratch didn’t work out for me right away. Honestly, I tried to make friends with him (I had to pass the exam somehow). But when studying its basics, it seemed callous and even cold to me.

In general, I took up ASP.NET. I created my first website. Well, everything seems to be working in the development environment. Cross-browser compatibility checked in several popular browsers. I think it's time to "fight." So to speak, show your “brainchild” to the whole country (at least). This is where the “rakes” turned out to be.

My attempts to find hosting with ASP.NET support on the RuNet were never successful. There were, of course, several paid platforms, but the prices for hosting a website on them were clearly not “student” prices.

Somehow I dug up in Burzhunet free option hosting (by the way, sponsored by Microsoft). Well, I clicked, enjoyed the breadth of my thoughts, but things didn’t go any further. And all due to the fact that most of the sites were already made in PHP.

After you decide and understand for sure that you are ready to learn the PHP programming language, look for a tutorial for beginners “for yourself.” The main thing is that you understand what the author of the publication wants to convey to his readers. Immediately get ready to pay a good amount of money for quality literature.

But it’s better to take an integrated approach - add a smart one too. This will allow you to hone your skills right away practical examples. And my advice to you is to do less copy-pasting code! I’ll explain why now.

When you type example scripts yourself, you will quickly get used to and remember the features of PHP syntax. As for literature, choose a tutorial with the basics of programming in PHP. And it is advisable that the author post the code of all the examples given on his resource on the Internet.

Also, immediately before starting training, download and install Open Server. This software package includes all the environments you need to write and test code.

Well, let me take my leave for today. Forgive (if anything) for the excessive overview of the content of the article, but this is necessary to understand the features of this language (after all, it is server-based). I wish you to quickly grasp the basics of the PHP programming language and start real coding!

PHP programming language - Training course - Savelyeva N.V. - 2006.

PHP is currently one of the most popular languages ​​for implementing web applications. This course is devoted to studying its basics. The emphasis is on practical use acquired skills.
The PHP language was created to solve a specific practical problem on the Internet (which one can be found out by reading the first lecture of the course). We will also try not to be distracted too much by theoretical reasoning, and will strive to solve a specific problem in each of the lectures. Most examples are taken from real life existing system: virtual museum of the history of computer science. The first part of the course is devoted to studying the basics of syntax and control structures. After this, client-server technology is considered as the main application area of ​​the PHP language. Then we move on to studying the most useful built-in functions in our opinion and solving practical problems with their help. Although the object model in PHP language not the richest, its fundamental presence allows us to naturally describe object models data. As a basic model, the document model of a virtual computer science museum will be considered. After this, a number of applied aspects will be considered: working with file system, with a database, strings, sessions, DOM XML - all this will allow you to consider key tasks practical use language.

PHP, MySQL for beginners - Andy Harris - 2005.

This book will help you learn how to program in PHP and create databases in MySQL. If your goal is to write programs for web servers, then this book is for you. You will learn all the basic concepts of programming languages, in particular, learn the commands and syntax of the PHP language. You will also learn how data is used in modern environments, in addition to all this, you will also learn the programming process itself.


Download and read PHP, MySQL for beginners - Andy Harris

PHP - Learning by Example - Kuharchik A.

PHP - Learning by Example - Kukharchik A. - 2004.

The basics of PHP, a popular language for writing scripts for Web pages, are presented in a simple and accessible way. By completing simple examples, the reader will be able to master the basics of programming in PHP, create dynamic page, site visit counter, voting system, address book, Online store. Described typical mistakes use of scripts, as well as ways to correct them. The book contains code snippets that you can use to create your own projects.

Intended primarily for beginners, but can also be useful for experienced programmers using PHP.

I present to your attention a free translation of the article 30+ PHP Best Practices for Beginners

PHP is the most widely used programming language for the Internet. Here's thirty best advice for beginners, which will help you firmly grasp the basics.

1. Make friends with the PHP manual

If you are a beginner in PHP, then it's time to check out the amazing PHP tutorial. The PHP Guide is incredibly comprehensive and has really helpful comments on each article. Before asking questions or attempting to resolve an issue yourself, contact management directly. There is a good chance that the answer to your question is already contained in articles on the PHP.net website.

2. Enable error output

6. Use indentation and white space for readability

If you don't use indentation and whitespace in your code, the result looks like the art of Jackson Pollack (an American artist, ideologist and leader of abstract expressionism who had a significant influence on the art of the second half of the 20th century). Make sure your code is readable and easy to find the right piece code, because most likely you will have to modify it in the future. IDE and advanced text editors can add indents automatically.

7. Stagger your code

This means nothing more than separation different components code into separate parts. This will make it easy to change the code in the future.

8. Always use

Often programmers try to use a shortened form of the declaration PHP scripts. Here are some examples:

<% echo "Hello world"; %>

While this does shorten the entry by a few characters, all of these methods remain for compatibility reasons and are unofficial. Stick to the standardthis will ensure support in all future versions.

9. Use meaningful names that follow naming conventions

Naming is not just for your benefit. There's nothing worse than trying to find something in meaningless variable names. Help yourself and others by using meaningful names for your classes and functions.

10. Comments, Comments, Comments

Apart from using indentation and code separation, you can also use comments to describe your code. You'll thank yourself later when you need to go back and find something in the code, or when you can't remember what a certain function does. This will also be useful to everyone who will view your code.

11. Install MAMP/WAMP

MySQL is the most popular server database used with PHP (if not the only one). If you want to organize local environment development for testing their PHP application, take a look at MAMP (Mac) or WAMP (Windows). Installing MySQL on your computer can be quite a tedious process, and both of these packages already contain MySQL. Clean and simple.

12. Limit your scripts

It is a good practice to set a time limit for the execution of your PHP scripts. There are times when a script will crash, and if this happens, you may want to use a script time limit to prevent errors associated with infinite loops and database connection timeouts. set_time_limit allows you to set a limit on the script execution time in seconds (by default this value is 30). After this time is exceeded, a fatal error is generated.

13. Use objects (or OOP)

14. Distinguish between double and single quotes

It's most effective to use single quotes in strings where you don't need to parse "escaped" characters and anything else that might be contained in double quotes. Use single quotes wherever possible

Note: This is actually not entirely true. Tests show that if the string does not contain variables, then double quotes give a performance gain.

15. Don't put phpinfo() in your server root directory

(displays information about PHP interpreter) this is a wonderful thing. Create simple PHP file with this content

and put it somewhere on the server, you will be able to see comprehensive information about your server. However, many beginners place the file containing phpinfo() in the root directory of the web server. This is really not safe; anyone who sees information about the server can potentially harm it. Make sure phpinfo() is in a safe place, or better yet, remove it.

16. Never trust users

If your application has fields for user input, then you must assume that the user will try to enter dangerous code. (This does not mean that all users are malicious. It's just better to think so.) To avoid hacking attempts, always try to initialize your variables with the following lines.

17. Keep passwords encrypted

Many novice PHP programmers store important data in a database, such as passwords, in open form. Let's see how to use MD5 to encrypt passwords before writing them to the database.

Echo md5("myPassword"); // will print -

Note: Keep in mind that MD5 hashes have already been cracked. They add security, but an attacker can decrypt the hash using rainbow tables. To increase safety, add salt. "Salt" adds additional characters to the user string.

18. Use database visualization tools

If you are having difficulty executing and changing data in PHP when working with a database, try using visual aids. MySQL users can use DBDesigner and MySQL Workbench to display data in the database.

19. Use buffered output

Buffered output is a simple way to improve the performance of your PHP scripts. Without buffered output, your scripts render HTML in chunks. By adding buffered output, PHP stores the HTML code as a variable and outputs it to the browser in one piece.

To enable output buffering, simply add ob_start() at the beginning of the file.

Note: It is considered in good form add function ob_end_flush(); to the end of the document. P.S. Want to compress HTML? Just replace ob_start(); on ob_start("ob_gzhandler");

Behind additional information contact here

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20. Protect scripts from SQL injections

If you don't use character escaping in terms with SQL queries, then your application is susceptible to SQL injections. You can avoid this by using mysql_real_escape_string, or prepared (precompiled) queries.

Example of using mysql_real_escape_string:

$username = mysql_real_escape_string($GET["username"]);

and the prepared line:

$id = $_GET["id"]; $statement = $connection->prepare("SELECT * FROM tbl_members WHERE id = ?"); $statement->bind_param("i", $id); $statement->execute();

By using prepared constructs, we prevent user data from being written directly to the request. Instead, we use the "bind_param" method to bind values ​​to variables in the query. More secure, faster, especially when executing multiple CRUD (create read) statements update delete- “Creating reading updating deleting” - approx.) at a time.

21. Use ORM

If you write object-oriented code in PHP, you can use an object-relational mapping (ORM). ORM allows you to transform data between relational base data and object-oriented programming language. In short: ORM allows you to work with a database in the same way as with classes and objects in PHP.

One of many ORM libraries for PHP Propel, as well as ORM is present in PHP frameworks, for example in CakePHP.

22. Cache pages that use a database

Caching pages that use the database reduces the load and improves script performance. This allows you to create and use static files using the ob_start() function. Example from Snipe.net:

// start of the script $cachefile = "cache/".basename($_SERVER["SCRIPT_URI"]); $cachetime = 120 * 60; // 2 hours // use cache if value is less than $cachetime if (file_exists($cachefile) && (time() - $cachetime< filemtime($cachefile))) { include($cachefile); echo ""; exit; ) ob_start(); // start of buffered output // your script and HTML should go here // end of script $fp = fopen($cachefile, "w"); // open cache file for writing fwrite($ fp, ob_get_contents()); // save the contents of the buffered output to a file fclose($fp); // close the file ob_end_flush(); // send the data to the browser

This part of the code uses a cached version of the page if the page is not “older” than 2 hours.

23. Use caching systems

If you want to use more reliable system caching than the above script, use the following PHP scripts.

  • Netbeans has PHP profiling capabilities.

    27. Coding Standards

    Once you are comfortable with PHP, you can move on to learning coding standards. There are differences between standards (Zend, Pear), choose yours and stick to it always.

    28. Keep functions out of loops

    You kill performance when you put functions in a loop. The longer the cycle, the more time fulfillment you get. If you want to reduce execution time, remove functions from loops.

    Note: Using this logic, try to move as many operations out of the loop as possible. Think about it: do you really need to create a variable every time you loop? Do I need to call the function every time? Of course not:)

    29. Don’t create variables

    Some people, for code clarity, copy the values ​​of predefined variables into variables with short names. This leads to redundancy and potentially doubles the memory consumption of your script. Here are examples of bad and good use variables:

    $description = strip_tags($_POST["description"]); echo $description;

    Echo strip_tags($_POST["description"]);

    Note: Talking about doubling memory consumption is actually misleading. PHP implements memory management using a copy-on-write approach. This means you can assign the same value to multiple variables and not have to worry about duplicate data in memory. One could argue that a "good" example good example good code, however, it is definitely not faster.

    30. Update to the latest version of PHP

    Although this seems reasonable, many people don't update PHP when they should. PHP 5 is more powerful than PHP 4. Check your server and make sure you have the latest version.

    31. Reduce the number of database queries

    The fewer queries to the database, the greater the performance of the PHP script. Utilities such as Stace (Unix) and Process Explorer (Windows) will help you find redundant processes and eliminate them.

    32. Don't be afraid to ask

    Only people try to hide the fact of their ignorance in a certain area. Nobody wants to seem stupid! But how can we learn without asking? Feel freer using the forums and IRC StackOverflow, ask experienced PHP developers. There is a page on the PHP website

Internet in modern world occupies an increasingly stronger position. About 15 years ago, access to the network required expensive equipment and a lot of money to pay bills. Nowadays anyone can get on the Internet for pennies if they have at least mobile phone. More and more services are moving to electronic form. From a means of communication and information exchange, the Internet is turning into handy tool to do business and make money.

Every day, millions of users visit their favorite sites, download email, files or news, play online games, conduct company business, or simply communicate in chat rooms, blogs and forums. Most of these users have never thought about how it all works, who creates new sites and services, how and with what help.

This electronic textbook is intended for those for whom it is not enough to simply surf the Internet. For those who want to learn how to create their own websites and keep up with the latest trends in programming and design.

General principles

Before you start learning a language, you need to clearly define the terminology and understanding general principles operation of the Internet. Let's start with the principles of the network and sites.

The Internet consists of a huge number of interconnected computers, routers and other hardware needed for proper operation. Each element of the Internet (node) has a unique descriptor - an IP address. Knowing the IP address of a node, you can try to connect to it, and with a little skill you can determine who this address belongs to and in what region of the world it is located. IP addresses are usually written in as four groups of numbers separated by dots, for example

192.168.100.003 or 10.10.0.123

Agree, remembering the addresses of all frequently visited pages is not an easy task. Therefore, there are special DNS server(Domain Name Resolution), which stores mapping lists of IP addresses and symbolic names. It is thanks to these servers that the user always gets to the desired IP address by typing only the page name in the browser.

After we have entered the name of the desired page into the browser line, the browser independently receives the IP address from the DNS the desired server and sends it to this address special request to receive a page (HTTP request). Running on a server specialized program(the so-called Web server) processes this request and returns the required page to the browser.

Obviously, all actions for displaying a page can be clearly divided into two categories: those performed on the client side ( client code or front-end) and executed on the server side ( server code or back-end). Moreover, the server knows nothing about the current state of the client, and the client knows nothing about the current state of the server. When developing exchange algorithms, you must always remember this and timely transmit the necessary data describing the state or required action.

Depending on the place of application, the means of implementing the parts also differ. On the client side, typically only HTML, JavaScript (AJAX), CSS and Flash are used. Server-side developers are less strapped for money, because... Most existing languages ​​allow you to create or describe HTML pages. The most widely used today are Java, Perl, PHP, Python, Ruby, C# and VB.NET. Each of them has its own strengths and weak sides, so the developer must make a choice based on the tasks facing him.

Why PHP?

There are a large number of languages ​​that can be used when creating websites. Some languages ​​have existed for a long time and are successfully used (or no longer used). Some languages ​​are still very young and have not yet received widespread use. Lastly PHP time became a leader in popularity, for several reasons:

  1. Simplicity. The language is very easy to understand, especially for novice programmers.
  2. Development speed. Thanks to its simplicity and intuitiveness, PHP allows you to create quite complex websites very quickly.
  3. Availability of libraries Exists great amount ready-made examples and class libraries. Hundreds of libraries have been created and tested to significantly simplify the life of a developer.
  4. Support Almost every server on the Internet supports PHP
  5. Safety PHP allows you to create truly secure websites thanks to its built-in support for data encryption during storage and transmission.

However, PHP pays for its benefits with some limitations. For example, use PHP to access system functions very inconvenient compared to Perl or Python (which is why many system administrators love Perl so much). There are several other limitations that we will talk about when studying the relevant sections.


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