What Is The Question Mark In Php?


In PHP 7, the double question mark(??) operator known as Null Coalescing Operator. It returns its first operand if it exists and is not NULL; otherwise, it returns its second operand. It evaluates from left to right.



What is the question mark in PHP?

In PHP 7, the double question mark(??) operator known as Null Coalescing Operator. It returns its first operand if it exists and is not NULL; otherwise, it returns its second operand. It evaluates from left to right.


Which is the concatenation operator in PHP?

The first is the concatenation operator ('. '), which returns the concatenation of its right and left arguments. The second is the concatenating assignment operator (' . = '), which appends the argument on the right side to the argument on the left side.


How do developers make a test a good test?

5 Main Characteristics of a Good Psychological Test

  1. Objectivity: The test should be free from subjective—judgement regarding the ability, skill, knowledge, trait or potentiality to be measured and evaluated.
  2. Reliability:
  3. Validity:
  4. Norms:
  5. Practicability:


What is the number 1 portable generator?

Best Portable Generator for Home Use

Generac's GP6500 is an all-around great generator. Its 6500 running watts and 8125 starting watts are more than you get from the small 5000-watt class. It provides plenty of power and enough outlets to run just about anything on 120V. Plus, it has a 120V/240V plug if you need it.


What is MTU in EIGRP?

MTU stands for Maximum Transmission Unit. It is advertised with the routing update but does not actively participate in the metric calculation. EIGRP uses it when the number of similar cost paths to the same destination exceeds the number of allowed paths.


How do you calculate mL HR?

Use the following equations: flow rate (mL/hr) = total volume (mL) ÷ infusion time (hr) infusion time (hr) = total volume (mL) ÷ flow rate (mL/hr)


What are the 4 primary mechanisms of biological evolution?

Those factors are natural selection, mutation, genetic drift, and migration (gene flow).


How many ways can you find the area of a triangle?

3 Methods to Calculate Area of Triangle

  1. Method 1: Using base and height.
  2. Method 2: Using side lengths.
  3. Method 3: Using trigonometry.


What is the full form of HTTP Mcq?

HTTP stands for Hypertext Transfer Protocol. Hypertext Transfer Protocol is an application protocol used for data communication.


How do I type math symbols in my browser?

Type mathematical symbols - online keyboard. Press Alt with the appropriate letter. For example, to type ⊂, ⊆ or ⊄, hold Alt and press C one, two or three times. Stop the mouse over each button to learn its keyboard shortcut.


Why do teachers need a rich mathematical vocabulary?

It is important that students are able to bounce ideas off of each other and discuss how they solved a problem or what they're thinking as they try to work it out. Knowing and understanding some of the “math words” can help students explain their thinking.


How do you start liking in physics?

How to enjoy physics: Dr Nemer's tips

  1. 1) Physics is better when you do not memorise anything.
  2. 2) Study of physics is often mis-identified as abstract and dry.
  3. 3) Physics is about asking questions and solving problems.


Can demand curve have a positive slope?

False, a demand curve does not have a positive slope. Explanation: The demand curve has a negative slope as it is a downward sloping curve from left to right.


Which is national tree?

Indian fig tree, Ficus bengalensis, whose branches root themselves like new trees over a large area. The roots then give rise to more trunks and branches. Because of this characteristic and its longevity, this tree is considered immortal and is an integral part of the myths and legends of India.


What are the different types of redox reactions Class 11?

Based on the nature of the reaction, redox reactions are divided into four types. They are combination reactions, decomposition reactions, displacement reactions and disproportionation reactions.


Is a two-dimensional shape?

Definition. 2D stands for 2-dimensional. 2-dimensional shapes are flat and only have two dimensions: length and width. They include squares, rectangles, circles, triangles, and more.


Why do marketers study consumer behaviour?

Study of consumer buying behavior is most important for marketers as they can understand the expectation of the consumers. It helps to understand what makes a consumer to buy a product. It is important to assess the kind of products liked by consumers so that they can release it to the market.


What is single-stage transistor amplifier?

Single-stage Transistor Amplifier

When only one transistor with associated circuitry is used for amplifying a weak signal, the circuit is known as single-stage amplifier. Analyzing the working of a Single-stage amplifier circuit, makes us easy to understand the formation and working of Multi-stage amplifier circuits.


What is the formula for direct and inverse variation?

For direct variation, use the equation y = kx, where k is the constant of proportionality. For inverse variation, use the equation y = k/x, again, with k as the constant of proportionality.


Who is the most powerful lady in the world?

MacKenzie Scott

Philanthropist MacKenzie Scott is ranked the world's most powerful woman by Forbes.


Dated : 11-Jun-2022

Category : Education

Leave Your Comment