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In this article, we're going to explore how you could use a MySQL database to perform CRUD (create, read, update, and delete) operations with PHP. If you want to get your hands dirty with database connectivity in PHP, this article is a great starting point. If you are just getting started with PHP, you probably realize that database connectivity is an essential feature that you'll need to get familiar with sooner or later. In most cases, a database is the backbone of any web application and holds the data of the application. So, as a PHP developer, you'll need to know how to deal with database operations. In this article, we'll keep things simple and explore how to use the core mysqli functions. In upcoming articles of this series, we'll explore a couple of other ways to handle database connectivity. Today, we'll go through the basics of database connectivity in PHP, and we'll use the MySQL database as our database back-end. Let's have a quick look at...

Adding the date and time to the WordPress Loop seems like a simple enough task, right? Well, yes. It can be a case of coding a simple template tag and letting WordPress do the work for you. But sometimes you can run into problems along the way. In this quick tip, I'll show you the different functions WordPress gives you for displaying the date and time, and tell you which ones to use if you run into snags. The Available Template Tags WordPress gives you four functions to output the date and/or time. These are: the_date() .  By default it will echo the date of the post in the format  F j, Y , so if the post was published on 20 November 2018, it would echo November 20, 2018 . get_the_date() - this fetches the date and doesn't echo it out. To echo it, you'd use echo get_the_date() which gives you the same result as the_date() . It's useful if you're already using echo in your code. It can also help you get round the problem of dates not being displayed, as yo...

Let me begin this post by saying that almost no event is truly random. Even the outcome of a classic coin toss could in theory be predicted if we knew the effect of every factor involved, like air friction, gravity, and initial force. The same thing is applicable to the generation of random numbers and alphanumeric strings. The best we can hope for is to generate numbers and strings that don't seem to follow a pattern and can't be practically predicted by an attacker.  In this tutorial, we will cover different techniques for generating random numbers and alphanumeric strings in PHP. Some of them will be cryptographically secure, while others are meant only for casual use, like assigning pseudo-random file names or creating URLs and suggesting usernames. Generating Random Numbers in PHP There are three different functions for generating random numbers in PHP. All of them will accept a minimum and maximum possible value for the random numbers and output a random number for yo...

A constant challenge faced by front-end developers is the performance of our applications. How can we deliver a robust and full-featured application to our users without forcing them to wait an eternity for the page to load? The techniques used to speed up a website are so numerous that it can often be confusing to decide where to focus our energy when optimising for performance and speed. Thankfully, the solution isn't as complicated as it sometimes might seem. In this post I'll breakdown one of the most effective techniques used by large web apps to speed up their user experience. I'll go over a package to facilitate this and ensure that we can deliver our app to users faster without them noticing that anything has changed. What Does it Mean for a Website to be Fast? The question of web performance is as deep as it is broad. For the sake of this post I'm going to try and define performance in the simplest terms:  send as little as you can as fast as you can. Of c...

Transitions and animations are an important design pattern whose aim is to improve the user experience (UX) by making the user interface (UI) more natural and intuitive.  Most people think that the purpose of transitions and animations is to engage the user's attention, and this is true to some extent. In certain contexts, such as game websites, where attractiveness and entertainment take precedent, it is justified. However, in most websites, engagement should be the secondary role, while the main role of any transitions or animations should be for communication. And that will be the subject of this tutorial. We'll explore how transitions and animations can communicate effectively, and we'll see how to use them in the context of Vue.js . Of course, to apply the principles discussed below, you can use any other library or framework (such as React or Angular), or plain CSS transitions and animations. Note: To follow this tutorial, you should have at least some basic knowle...

In this tutorial, you'll learn several important functions in PHP which are sufficient for all your basic file reading and writing needs. You'll learn how to read a file, write to a file, write to a text file, and check if a file exists. Luckily, PHP provides a lot of functions to read and write data to files. In this tutorial, I'll show you the easiest ways to read data from a local or remote file and how to use flags to write to files exactly how we want. Checking if a File Exists Your very first step when trying to read data from a file or writing something to it should be to check if the file already exists. Trying to read data from a file which does not exist will result in a warning from PHP and will probably crash your code. The easiest way to check if a file exists is to use the PHP file_exists($filename) function. It will return true if a file or directory with the given $filename exists and false otherwise. This might be obvious, but I would like to point ...