What Are the PHP Interview Questions?

What is PHP?

PHP is an open source, server-side scripting language used for web development. It's a general-purpose scripting language that comes with a lot of support for most popular databases (MySQL, PostgreSQL), as well as being installed on many web platforms. PHP is considered to be a dynamic, loosely typed language—meaning it can run in different environments and does not need to be compiled or compiled separately from its goal environment.

PHP is also very popular among developers because of its ease of use. Because of this popularity, there are many resources available online to help you learn how to program in PHP!

How does session work in PHP?

Session is a temporary storage for a user. It provides a mechanism to store and retrieve data from the server. Session works by assigning an ID to each visitor, that way you can keep track of the actions taken by them on your website or web application.

Each time someone visits your site, the session starts again and stores any data like shopping cart contents in memory so that it can be retrieved later without accessing database again.

What is the difference between session and cookie?

A cookie is a small text file that's stored on the user's computer. It allows a website to store information about a visitor and his or her activity on the site, so that it can be remembered later. For example, if you visited an online store and added items to your shopping cart but didn't check out immediately, then returned later to complete your purchase, cookies will track which items were stored in your cart before and allow you to easily complete the order process.

Cookie data can also be used for more analytic purposes—for instance, it could tell how many times someone has visited a site or what content they viewed most frequently. The data stored in cookies can also help determine which areas of a website need improvement (e.g., increase ad revenue).

Session variables are created by PHP scripts every time a page request is made by the end user (i.e., client). They allow two different variables ($var1 = "Hello" & $var2 = "World") from being accessed by multiple scripts running at once without overwriting each other's values (i

What are the different types of errors in PHP and what does each of them mean?

PHP comes with a lot of built-in error reporting levels. You can set these levels, and then each level will have an associated constant that you can use to check if an error has occurred. The following constants are used for setting the global error reporting level:

• E_WARNING

• E_NOTICE

• E_STRICT

• E_DEPRECATED

• E_USER_DEPRECATED

• E_USER_ERROR (deprecated in PHP 7) * _(In versions prior to PHP 5, this was `E__USER___TRAIT`) This is a user-defined fatal error that should not be caught by any application. If it occurs, the application should catch it and die().

How do you call a constructor for a parent class?

How do you call a constructor for a parent class?

• You can call the constructor with the parent class name. For example:

public function __construct() {}

• You can call the constructor with a parent class name and arguments. For example:

public function __construct($id) {}

• You can call the constructor with a parent class name, arguments and $this variable. For example:

public function __construct($id) { echo $this->getId(); }

How do you declare abstract functions and classes?

You can declare an abstract class using the keyword abstract and it will be inherited by all its subclasses.

You can also declare a function as abstract in your class. This means that it cannot be instantiated directly, but instead must be called from a subclass’s implementation of that function.

Know your stuff.

The best way to prepare for a PHP interview is to practice. A lot. You should do a lot of reading and coding, but you also need to think about the language and its capabilities, and talk through your ideas with other people. This can help you get more comfortable with the language, understand its quirks better, and even improve your problem-solving skills.

In fact, practicing will be part of every step in preparing for an interview!