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PHP Assignment Operators

Summary : in this tutorial, you will learn about the most commonly used PHP assignment operators.

Introduction to the PHP assignment operator

PHP uses the = to represent the assignment operator. The following shows the syntax of the assignment operator:

On the left side of the assignment operator ( = ) is a variable to which you want to assign a value. And on the right side of the assignment operator ( = ) is a value or an expression.

When evaluating the assignment operator ( = ), PHP evaluates the expression on the right side first and assigns the result to the variable on the left side. For example:

In this example, we assigned 10 to $x, 20 to $y, and the sum of $x and $y to $total.

The assignment expression returns a value assigned, which is the result of the expression in this case:

It means that you can use multiple assignment operators in a single statement like this:

In this case, PHP evaluates the right-most expression first:

The variable $y is 20 .

The assignment expression $y = 20 returns 20 so PHP assigns 20 to $x . After the assignments, both $x and $y equal 20.

Arithmetic assignment operators

Sometimes, you want to increase a variable by a specific value. For example:

How it works.

• First, $counter is set to 1 .
• Then, increase the $counter by 1 and assign the result to the $counter .

After the assignments, the value of $counter is 2 .

PHP provides the arithmetic assignment operator += that can do the same but with a shorter code. For example:

The expression $counter += 1 is equivalent to the expression $counter = $counter + 1 .

Besides the += operator, PHP provides other arithmetic assignment operators. The following table illustrates all the arithmetic assignment operators:

Concatenation assignment operator

PHP uses the concatenation operator (.) to concatenate two strings. For example:

By using the concatenation assignment operator you can concatenate two strings and assigns the result string to a variable. For example:

• Use PHP assignment operator ( = ) to assign a value to a variable. The assignment expression returns the value assigned.
• Use arithmetic assignment operators to carry arithmetic operations and assign at the same time.
• Use concatenation assignment operator ( .= )to concatenate strings and assign the result to a variable in a single statement.

• Assignment Operators

PHP assignment operators enable you to frequently engage in performing calculations and operations on variables, requiring the assignment of results to other variables. Consequently, this is precisely where assignment operators prove indispensable, allowing you to seamlessly execute an operation and assign the result to a variable within a single statement.

In the following sections, we’ll delve into the different types of PHP assignment operators and explore how to use them.

Table of Contents

Php arithmetic assignment operators, php bitwise assignment operators.

• Null Coalescing Operator

Assigning a Reference to a PHP Variable

Other assignment operators, wrapping up.

The most commonly used assignment operator in PHP is the equals sign (=). For instance, in the following code, the value 10 is assigned to the variable $x:

Now, let’s explore each type with examples:

Numeric data undergoes mathematical operations through the utilization of arithmetic operators. In PHP, this is where arithmetic assignment operators come into play, employed to perform these operations. The arithmetic assignment operators include:

• += or $x + $y (Addition Assignment Operator)
• -= or $x - $y (Subtraction Assignment Operator)
• *= or $x * $y (Multiplication Assignment Operator)
• /= or $x / $y (Division Assignment Operator)
• %= or $x % $y (Modulus Assignment Operator)
• **= or $x ** $y (Exponentiation Assignment Operator)

Consider the following example:

In this example, the addition assignment operator increases the value of $x by 5, and then assigns the result back to $x, producing an output of 15.

You can leverage these arithmetic assignment operators to perform complex calculations in a single statement, making your code more concise and easier to read. For more details, refer to this tutorial .

One crucial aspect of computer science involves the manipulation of binary bits in PHP. Let’s delve into one of the more complex assignment operators—specifically, the PHP bitwise operators.

Developers use bitwise operators to manipulate data at the bit level. PHP bitwise assignment operators perform bitwise operations. Here are the bitwise assignment operators:

• &= or $x & $y (Bitwise AND Assignment Operator)
• |= or $x | $y (Bitwise OR Assignment Operator)
• ^= or $x ^ $y (Bitwise XOR Assignment Operator)
• ~= or $x ~ $y (Bitwise NOT Assignment Operator)
• <<= or $x << $y (Left Shift Assignment Operator)
• >>= or $x >> $y (Right Shift Assignment Operator)

Let’s illustrate with an example:

In this example, a bitwise OR operation is performed between the values of $x and 2 using the bitwise OR assignment operator. The result is then assigned to $x, yielding an output of 7.

Here is a full explanation along with more examples of bitwise operators .

Let’s move to the section below to understand the Null Coalescing Operator in PHP.

Furthermore, developers use the null coalescing operator to assign a default value to a variable if it is null. The double question mark (??) symbolizes the null coalescing operator. Consider the following example:

In this example, the null coalescing operator is used to assign the value ‘John Doe’ to the variable $fullName. If $name is null, the value ‘John Doe’ will be assigned to $fullName.

The null coalescing operator simplifies code by enabling the assignment of default values to variables. By reading this tutorial , you will gain more information about it

Anyway, assigning a reference in PHP is one of the language’s benefits, enabling developers to set a value and refer back to it anywhere during the script-writing process. Let’s move to the section below to take a closer look at this concept.

Furthermore, individuals use the reference assignment operator =& to assign a reference to a variable rather than copying the value of the variable. Consider the following example:

In this example, a reference to the variable $x is created using the reference assignment operator. The value 10 is then assigned to $x, and the output displays the value of $y. Since $y is a reference to $x, it also changes to 10, resulting in an output of 10.

The reference assignment operator proves useful when working with large data sets, enabling you to avoid copying large amounts of data.

Let’s explore some other assignment operators in the paragraphs below.

In addition to the arithmetic, bitwise, null coalescing, and reference assignment operators, PHP provides other assignment operators for specific use cases. These operators are:

• .= (Concatenation Assignment Operator)
• ??= (Null Coalescing Assignment Operator)

Now, let’s explore each of these operators in turn:

Concatenation Assignment Operator: Used to concatenate a string onto the end of another string. For example:

In this example, the concatenation assignment operator appends the value of $string2 to the end of $string1, resulting in the output “Hello World!”.

The Null Coalescing Assignment Operator is employed to assign a default value to a variable when it is detected as null. For example:

In this example, the null coalescing assignment operator assigns the value ‘John Doe’ to the variable $name. If $name is null, the value ‘John Doe’ will be assigned to $name.

Let’s summarize it.

we’ve taken a comprehensive look at the different types of PHP assignment operators and how to use them. Assignment operators are essential tools for any PHP developer, facilitating calculations and operations on variables while assigning results to other variables in a single statement.

Moreover, leveraging assignment operators allows you to make your code more concise, easier to read, and helps in avoiding common programming errors.

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Assignment Operators

The basic assignment operator is "=". Your first inclination might be to think of this as "equal to". Don't. It really means that the left operand gets set to the value of the expression on the right (that is, "gets set to").

The value of an assignment expression is the value assigned. That is, the value of " $a = 3 " is 3. This allows you to do some tricky things:

In addition to the basic assignment operator, there are "combined operators" for all of the binary arithmetic , array union and string operators that allow you to use a value in an expression and then set its value to the result of that expression. For example:

Note that the assignment copies the original variable to the new one (assignment by value), so changes to one will not affect the other. This may also have relevance if you need to copy something like a large array inside a tight loop.

An exception to the usual assignment by value behaviour within PHP occurs with object s, which are assigned by reference. Objects may be explicitly copied via the clone keyword.

Assignment by Reference

Assignment by reference is also supported, using the " $var = &$othervar; " syntax. Assignment by reference means that both variables end up pointing at the same data, and nothing is copied anywhere.

Example #1 Assigning by reference

The new operator returns a reference automatically, as such assigning the result of new by reference is an error.

The above example will output:

More information on references and their potential uses can be found in the References Explained section of the manual.

Arithmetic Assignment Operators

Bitwise assignment operators, other assignment operators.

• arithmetic operators
• bitwise operators
• null coalescing operator

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Matt Doyle | Elated Communications

Web and WordPress Development

PHP References: How They Work, and When to Use Them

19 November 2010 / 18 Comments

References are a very useful part of PHP and, for that matter, most other programming languages. However, references can be somewhat confusing when you first start learning about them.

This tutorial is a gentle introduction to references in PHP. You find out what references are, and how they work. You learn how to create and delete references, as well as pass references to and from functions. You also explore some other uses of references, and discover situations where PHP creates references automatically on your behalf.

What exactly is a reference, anyway?

A reference is simply a way to refer to the contents of a variable using a different name. In many ways, references are like file shortcuts in Windows, file aliases in Mac OS X, and symbolic links in Linux.

• Assigning by reference

An easy way to create a reference is known as assigning by reference . Consider the following simple example:

Here we’ve created a variable, $myVar , and given it a value of “Hi there”. Then we’ve assigned that value to another variable, $anotherVar . This copies the value from the first variable to the second.

We then changed the value stored in $anotherVar to “See you later”. Since the 2 variables are independent, $myVar still keeps its original value (“Hi there”), which we then display in the page. So far, so good.

Now, let’s change the above example to assign $myVar to $anotherVar by reference , rather than by value. To do this, we simply put an ampersand ( & ) after the equals sign:

Now you can see that $myVar ‘s value has also changed to “See you later”! What’s going on here?

Rather than assigning the value of $myVar to $anotherVar — which simply creates 2 independent copies of the same value — we’ve made $anotherVar a reference to the value that $myVar refers to. In other words, $myVar and $anotherVar now both point to the same value. So when we assign a new value to $anotherVar , the value of $myVar also changes.

Note that we could have changed the value of $myVar to “See you later” instead of changing $anotherVar , and the result would have been exactly the same. The 2 variables are, in effect, identical.

Removing a reference

You delete a reference using the unset() function, in the same way that you delete a regular variable.

When you unset a reference, you’re merely removing that reference, not the value that it references:

The value remains in memory until you unset all references to it, including the original variable:

Passing references to functions

References really come into their own when you start passing them as arguments to functions. Normally, when you pass a variable to a function, the function receives a copy of that variable’s value. By passing a reference to a variable, however, the function can refer to — and, more importantly, modify — the original variable.

To pass an argument by reference, you place an ampersand before the parameter name when you define the function:

Now, whenever you call myFunc() and pass a variable to it, PHP passes a reference to the variable, rather than the variable’s value.

Let’s look at a simple example of passing by reference:

Here we created a function, goodbye() , that accepts a reference to a variable. The reference is stored in the parameter $greeting . The function assigns a new value (“See you later”) to $greeting , which changes the value stored in the variable that was passed to the function.

We test this out by creating a variable, $myVar , with an initial value of “Hi there”, and calling goodbye() , passing $myVar by reference. goodbye() then changes the value stored in $myVar to “See you later”.

So, use pass-by-reference whenever you want a function to change a variable that’s passed to it. Simple!

By the way, don’t be tempted to put an ampersand before the argument name in your function call:

The ampersand before the parameter in the function definition is sufficient to pass the variable by reference.

Many built-in PHP functions use pass-by-reference. For example, the sort() function accepts a reference to the array to sort, so that it can change the order of the elements in the array.

Returning references from functions

As well as passing references to functions, you can return references from functions. To do this, place an ampersand before the function name when you define the function. You should also use assign-by-reference ( =& ) when assigning the returned reference to a variable, otherwise you’ll merely assign the value, not the reference. Here’s an example:

In this example, our getNumWidgets() function retrieves the global variable $numWidgets and returns a reference to it. We then call getNumWidgets() , store the returned reference in $numWidgetsRef , and decrement the value that $numWidgetsRef points to. This is the same value that is pointed to by $numWidgets , as you can see by the results of the echo statements.

You probably won’t use return-by-reference as often as pass-by-reference, but it can be useful in certain situations, such as when you want to write a finder function (or class method) that finds a variable (or class property) and returns a reference to the variable or property, so that the calling code can then manipulate the variable or property.

Using references to change values in foreach loops

Another handy use of references is to change values in an array when using a foreach loop. With a regular foreach loop, you’re working with copies of the array values, so if you change a value you’re not affecting the original array. For example, let’s try to change an array of band names to uppercase with a foreach loop:

The above example displays:

As you can see, the original array has not been changed by the foreach loop. However, if we place an ampersand before $band in the foreach statement then $band becomes a reference to the original array element, rather than a copy. We can then convert the array elements to uppercase:

Our code now runs as intended, producing this:

Another way to change array values in a loop is to use a for loop instead of foreach .

When references are used automatically

So far you’ve looked at 4 ways to create references explicitly:

• Passing by reference
• Returning by reference
• Creating a reference in a foreach loop

In addition, there are occasions when PHP automatically creates references for you. Most of the time you won’t care, but it can be useful to know this stuff!

When using the global keyword

When you use global to access a global variable within a function, you are in fact creating a reference to the global variable in the $GLOBALS array. So:

does the same thing as:

When using $this

When you use the $this keyword within an object’s method to refer to the object, then it’s worth remembering that $this is always a reference to the object, rather than a copy of it. For example:

Since $this is a reference to the object in the above example, the method is able to change a property within the object to a new value.

When passing objects around

Unlike other types of variable, whenever you assign, pass, or return an object, you’re passing a reference to the object, not a copy. This is usually what you want to happen, since the function or method you pass an object to usually needs to work on the actual object, not a copy of it. For example:

In the few situations when you do actually want to make a copy of an object, you can use the clone keyword.

In fact, things are a bit more subtle than this. When you create an object variable, that variable merely contains a pointer to the object in memory, not the object itself. When you assign or pass that variable, you do in fact create a copy of the variable. But the copy is also merely a pointer to the object — both copies still point to the same object. Therefore, for most intents and purposes, you’ve created a reference.

In this tutorial you’ve learned the fundamentals of variable references in PHP. You’ve explored assigning, passing, and returning variables by reference; learned how to use references to change array elements in a foreach loop; and looked at situations where PHP creates references for you automatically.

If you’d like to learn more, check out the References Explained section of the PHP website. Have fun! 🙂

Reader Interactions

4 December 2010 at 2:41 pm

Thanks, Brilliant tutorial, Very well explained.

6 December 2010 at 9:31 pm

@akk: Thanks for the feedback – I’m glad you found the tutorial helpful. 🙂 References can be a tricky topic!

14 October 2011 at 11:15 am

A great learning web forum ever I came across.

11 October 2013 at 6:01 am

Excellent! Thanks for showing real use examples.

29 October 2016 at 5:59 am

Thank you man for this great effort, this tutorial explains the topic easily and professionally.

25 April 2019 at 1:10 pm

thanks that is very comlete

18 May 2019 at 4:34 am

Thank you, Matt!! I have needed a clear explanation of this, and here it is 🙂

22 May 2019 at 11:50 pm

You’re welcome Erin, glad it helped 🙂

14 September 2019 at 7:04 pm

Thank you very much, only after your tutorial I understood the “References” topic. Had a hard time with it before. Thank you, best wishes!

17 September 2019 at 8:45 am

You’re welcome 🙂

27 June 2020 at 3:33 pm

Thanks for this article, with examples very easy to understand. Helpful to understand the references, that can be a little abstract.

1 July 2020 at 12:08 am

You’re welcome, Joseph 🙂

19 July 2020 at 4:55 am

Thank you very much for this useful explanation, Matt.

One thing that I did note was that for me, your &getNumWidgets() example of the use of a global variable did not work in my WordPress site–specifically in my Enfold theme. I had to declare the $numWidgets variable as global outside the function for the function’s reference to it to work:

I’ve seen other posts elsewhere talk about how you have to do this with some plugins.

Thanks again!

29 July 2020 at 4:25 am

Thanks for your reply Gary! Yes, that’s probably because your code is being called from inside another function in the Enfold theme, and therefore you need to declare that variable as global in that scope also.

18 November 2020 at 9:50 am

Thank you Matt!

You explained very clearly so that even a junior level programmer can easily understand the concept of references and avoid the confusions.

18 November 2020 at 10:11 am

Thanks Ahmed ?

30 April 2021 at 12:40 am

thank you so much for this great explanation !

16 January 2023 at 7:20 pm

outstanding explainer, thanks!

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• Language Reference

Variables in PHP are represented by a dollar sign followed by the name of the variable. The variable name is case-sensitive.

Variable names follow the same rules as other labels in PHP. A valid variable name starts with a letter or underscore, followed by any number of letters, numbers, or underscores. As a regular expression, it would be expressed thus: ^[a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*$

Note : For our purposes here, a letter is a-z, A-Z, and the bytes from 128 through 255 ( 0x80-0xff ).

Note : $this is a special variable that can't be assigned. Prior to PHP 7.1.0, indirect assignment (e.g. by using variable variables ) was possible.

See also the Userland Naming Guide .

For information on variable related functions, see the Variable Functions Reference .

<?php $var = 'Bob' ; $Var = 'Joe' ; echo " $var , $Var " ; // outputs "Bob, Joe" $ 4site = 'not yet' ; // invalid; starts with a number $_4site = 'not yet' ; // valid; starts with an underscore $täyte = 'mansikka' ; // valid; 'ä' is (Extended) ASCII 228. ?>

By default, variables are always assigned by value. That is to say, when you assign an expression to a variable, the entire value of the original expression is copied into the destination variable. This means, for instance, that after assigning one variable's value to another, changing one of those variables will have no effect on the other. For more information on this kind of assignment, see the chapter on Expressions .

PHP also offers another way to assign values to variables: assign by reference . This means that the new variable simply references (in other words, "becomes an alias for" or "points to") the original variable. Changes to the new variable affect the original, and vice versa.

To assign by reference, simply prepend an ampersand (&) to the beginning of the variable which is being assigned (the source variable). For instance, the following code snippet outputs ' My name is Bob ' twice: <?php $foo = 'Bob' ; // Assign the value 'Bob' to $foo $bar = & $foo ; // Reference $foo via $bar. $bar = "My name is $bar " ; // Alter $bar... echo $bar ; echo $foo ; // $foo is altered too. ?>

One important thing to note is that only named variables may be assigned by reference. <?php $foo = 25 ; $bar = & $foo ; // This is a valid assignment. $bar = &( 24 * 7 ); // Invalid; references an unnamed expression. function test () { return 25 ; } $bar = & test (); // Invalid. ?>

It is not necessary to initialize variables in PHP however it is a very good practice. Uninitialized variables have a default value of their type depending on the context in which they are used - booleans default to false , integers and floats default to zero, strings (e.g. used in echo ) are set as an empty string and arrays become to an empty array.

Example #1 Default values of uninitialized variables

Relying on the default value of an uninitialized variable is problematic in the case of including one file into another which uses the same variable name. E_WARNING (prior to PHP 8.0.0, E_NOTICE ) level error is issued in case of working with uninitialized variables, however not in the case of appending elements to the uninitialized array. isset() language construct can be used to detect if a variable has been already initialized.

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PHP References Assign by Reference

Fastest entity framework extensions.

This is the first phase of referencing. Essentially when you assign by reference , you're allowing two variables to share the same value as such.

$foo and $bar are equal here. They do not point to one another. They point to the same place ( the "value" ).

You can also assign by reference within the array() language construct. While not strictly being an assignment by reference.

Note , however, that references inside arrays are potentially dangerous. Doing a normal (not by reference) assignment with a reference on the right side does not turn the left side into a reference, but references inside arrays are preserved in these normal assignments. This also applies to function calls where the array is passed by value.

Assigning by reference is not only limited to variables and arrays, they are also present for functions and all "pass-by-reference" associations.

Assignment is key within the function definition as above. You can not pass an expression by reference, only a value/variable. Hence the instantiation of $a in bar() .

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• Variable Assignment, Expressions, and Operators

Variables are containers for storing information, such as numbers or text so that they can be used multiple times in the code. Variables in PHP are identified by a dollar sign ($) followed by the variable name. A variable name must begin with a letter or the underscore character and only contain alphanumeric characters and underscores. A variable name cannot contain spaces. Finally, variable names in PHP are case-sensitive.

• Post author By BrainBell
• Post date May 12, 2022

This tutorial covers the following topics:

• Define a variable
• Assign a variable by reference
• Assign a string value to a variable

Assignment Operators

• Arithmetic Operators (See Comparison Operators and Logical Operators on Conditional Expression Tutorial).

Operator precedence

Expressions, define a variable.

PHP uses the  =  symbol as an assignment operator. The variable goes on the left of the equal sign, and the value goes on the right. Because it assigns a value, the equal sign is called the  assignment operator .

$ variableName = 'Assigned Value' ;

You can break the above example into the following parts:

• A dollar sign $ prefix
• Variable name
• The assignment operator (equal sign = )
• Assigned value
• Semicolon to terminate the statement

A PHP variable must be defined before it can be used. Attempting to use an undefined variable will trigger an error exception:

In PHP, you do not need to declare a variable separately before using it. Just assign value to a variable by using the assignment operator (equals sign = ) to make it defined or initialized:

A defined variable can be used by referencing its name, for example, use the print or echo command (followed by the variable’s name) to display the value of the variable on the web page:

Variable names are case-sensitive in PHP, so  $Variable , $variable , $VAriable , and $VARIABLE are all different variables.

Text requires quotes

If you look closely at the PHP code block in the above example, you’ll notice that the value assigned to the second variable isn’t enclosed in quotes. It looks like this:

Then the ‘BrainBell.com’ did use quotes, like this:

The simple rules are as follows:

• The text requires quotes (single or double)
• No quotes are required for numbers,  True ,  False  and  Null

Assign a string value to a variable:

Concatenate two strings together to produce “test string”:

Add a string to the end of another to produce “test string”:

Here is a shortcut to adding a string to the end of another:

Assign by reference

By default, PHP assigns all variables other than objects by value and not by reference. PHP has optimizations to make assignment by value faster than assigning by reference, but if you want to assign by reference you can use the  &  operator as follows:

The assignment operator (equal = ) can be combined with other operators to make it easier to write certain expressions. See the following table:

These operators assign values to variables. They start with the assignment operator = and move on to += , -= , etc.(see above table). The operator += adds the value on the right side to the variable on the left:

Arithmetic Operators

Using an operator, you can manipulate the contents of one or more variables or constants to produce a new value. For example, this code uses the addition operator (  +  ) to add the values of  $x  and  $y  together to produce a new value:

So an operator is a symbol that manipulates one or more values, usually producing a new value in the process. The following list describes the types of arithmetic operators:

Sum integers to produce an integer:

The values and variables that are used with an operator are known as operands.

Subtraction, multiplication, and division might have a result that is a float or an integer, depending on the initial value of $var :

Multiply to double a value:

Halve a value:

These work with float types too:

Get the remainder of dividing 5 by 4:

4 exponent (or power) of 2:

These all add 1 to $var:

And these all subtract 1 from $var:

If the  --  or  ++  operator appears before the variable then the interpreter will first evaluate it and then return the changed variable:

If the  --  or  ++  operator appears after the variable then the interpreter will return the variable as it was before the statement run and then increment the variable:

There are many mathematical functions available in the math library of PHP for more complex tasks. We introduce some of these in the next pages.

The precedence of operators in an expression is similar to the precedence defined in any other language. Multiplication and division occur before subtraction and addition, and so on. However, reliance on evaluation orders leads to unreadable, confusing code. Rather than memorize the rules, we recommend you construct unambiguous expressions with parentheses because parentheses have the highest precedence in evaluation.

For example, in the following fragment  $variable  is assigned a value of 32 because of the precedence of multiplication over addition:

The result is much clearer if parentheses are used:

But the following example displays a different result because parentheses have the highest precedence in evaluation.

An expression in PHP is anything that evaluates a value; it is a combination of values, variables, operators, and functions that results in a value. Here are some examples of expressions:

An expression has a value and a type; for example, the expression  4 + 7  has the value  11  and the type  integer,  and the expression "abcdef" has the value  abcdef  and the type  string . PHP automatically converts types when combining values in an expression. For example, the expression 4 + 7.0 contains an integer and a float; in this case, PHP considers the integer as a floating-point number, and the result is a float. The  type conversions  are largely straightforward; however, there are some traps, which are discussed later in this section.

Getting Started with PHP:

• Introducing PHP
• PHP Development Environment
• Delimiting Strings
• Variable Substitution

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Reference assignment operator in PHP to assign a reference?

Let’s say we have the following value −

Let us take a new variable and assign a reference −

To assign a reference, use the reference assignment operator i.e. =&$anyVariableName in PHP.

The PHP code is as follows −

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More than 321,000 U.S. children lost a parent to drug overdose from 2011 to 2021

Federal study shows lives lost from overdose crisis are felt across generations, emphasizing need to include children and families in support

An estimated 321,566 children in the United States lost a parent to drug overdose from 2011 to 2021, according to a study published in JAMA Psychiatry . The rate of children who experienced this loss more than doubled during this period, from approximately 27 to 63 children per 100,000. The highest number of affected children were those with non-Hispanic white parents, but communities of color and tribal communities were disproportionately affected. The study was a collaborative effort led by researchers at the National Institutes of Health’s (NIH) National Institute on Drug Abuse (NIDA), the Substance Abuse and Mental Health Services Administration (SAMHSA), and the Centers for Disease Control and Prevention (CDC).

Children with non-Hispanic American Indian/Alaska Native parents consistently experienced the highest rate of loss of a parent from overdose from 2011 to 2021 – with 187 per 100,000 children affected in this group in 2021, more than double the rate among non-Hispanic white children (76.5 per 100,000) and among non-Hispanic Black children (73 per 100,000). While the number of affected children increased from 2011 to 2021 across all racial and ethnic populations, children with young non-Hispanic Black parents (18 to 25 years old) experienced the highest – roughly 24% – increase in rate of loss every year. Overall, children lost more fathers than mothers (192,459 compared to 129,107 children) during this period.

“It is devastating to see that almost half of the people who died of a drug overdose had a child. No family should lose their loved one to an overdose, and each of these deaths represents a tragic loss that could have been prevented,” said Nora Volkow, M.D., NIDA director. “These findings emphasize the need to better support parents in accessing prevention, treatment, and recovery services. In addition, any child who loses a parent to overdose must receive the care and support they need to navigate this painful and traumatic experience.”

From 2011 to 2021, 649,599 people aged 18 to 64 died from a drug overdose. Despite these tragic numbers, no national study had previously estimated the number of children who lost a parent among these deaths. To address this gap, researchers used data about people aged 18 to 64 participating in the 2010 to 2019 National Surveys on Drug Use and Health (NSDUH) to determine the number of children younger than 18 years living with a parent 18 to 64 years old with past-year drug use. NSDUH defines a parent as biological parent, adoptive parent, stepparent, or adult guardian.

The researchers then used these data to estimate the number of children of the nearly 650,000 people who died of an overdose in 2011 to 2021 based on the national mortality data from the CDC National Vital Statistics System. The data were examined by age group (18 to 25, 26 to 40, and 41 to 64 years old), sex, and self-reported race and ethnicity.

The researchers found that among the estimated 321,566 American children who lost a parent to overdose from 2011 to 2021, the highest numbers of deaths were among parents aged 26 to 40 (175,355 children) and among non-Hispanic white parents (234,164). The next highest numbers were children with Hispanic parents (40,062) and children with non-Hispanic Black parents (35,743), who also experienced the highest rate of loss and highest year-to-year rate increase, respectively. The racial and ethnic disparities seen here are consistent with overall increases in overdose deaths among non-Hispanic American Indian/Alaska Native and Black Americans in recent years, and highlight disproportionate impacts of the overdose crisis on minority communities.

“This first-of-its-kind study allows us to better understand the tragic magnitude of the overdose crisis and the reverberations it has among children and families,” said Miriam E. Delphin-Rittmon, Ph.D., HHS Assistant Secretary for Mental Health and Substance Use and the leader of SAMHSA. “These data illustrate that not only are communities of color experiencing overdose death disparities, but also underscore the need for responses to the overdose crisis moving forward to comprehensively address the needs of individuals, families and communities.”

Based on their findings, the researchers emphasize the importance of whole-person health care that treats a person with substance use disorder as a parent or family member first and foremost, and provides prevention resources accordingly to support families and break generational cycles of substance use. The study also points to the need to incorporate culturally-informed approaches in prevention, treatment, recovery, and harm reduction services, and to dismantle racial and ethnic inequities in access to these services.

“Children who lose a parent to overdose not only feel personal grief but also may experience ripple effects, such as further family instability," said Allison Arwady, M.D., M.P.H., director of CDC’s National Center for Injury Prevention and Control. “We need to ensure that families have the resources and support to prevent an overdose from happening in the first place and manage such a traumatic event.”

If you or someone you know is struggling or in crisis, help is available. Call or text 988  or chat at  988lifeline.org . To learn how to get support for mental health, drug or alcohol issues, visit  FindSupport.gov . If you are ready to locate a treatment facility or provider, you can go directly to  FindTreatment.gov or call  800-662-HELP (4357) . 

• CM Jones, et al. Estimated Number of Children Who Lost a Parent to Drug Overdose, US, 2011-2021 . JAMA . DOI: 10.1001/jamapsychiatry.2024.0810 (2024).

About the National Institute on Drug Abuse (NIDA): NIDA is a component of the National Institutes of Health, U.S. Department of Health and Human Services. NIDA supports most of the world’s research on the health aspects of drug use and addiction. The Institute carries out a large variety of programs to inform policy, improve practice, and advance addiction science. For more information about NIDA and its programs, visit www.nida.nih.gov .

About the National Institutes of Health (NIH): NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov .

About substance use disorders: Substance use disorders are chronic, treatable conditions from which people can recover. In 2022, nearly 49 million people in the United States had at least one substance use disorder. Substance use disorders are defined in part by continued use of substances despite negative consequences. They are also relapsing conditions, in which periods of abstinence (not using substances) can be followed by a return to use. Stigma can make individuals with substance use disorders less likely to seek treatment. Using preferred language can help accurately report on substance use and addiction. View NIDA’s online guide .

NIH…Turning Discovery Into Health®

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Delta-8-THC use reported by 11% of 12th graders in 2023

Why Donald Trump ended up praising Hollywood’s most famous cannibal

During an angry speech in New Jersey, Trump allowed his exaggerations to overflow.

When Donald Trump is not reading the teleprompter, it’s hard to know what you’re going to get. Perhaps you’ll get the standard angry riffs about the things Trump has been saying he is angry about for the past nine years. Perhaps you’ll get an anecdote about how a big, strong man came up to Trump, tears in his eyes, and thanked the former president — “Sir, thank you!” — for what he did on whatever issue Trump had just talked about.

Or perhaps, as was the case in New Jersey this weekend, you’ll get a bit of praise for the murderous cannibal from the movie “Silence of the Lambs.”

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“The late, great Hannibal Lecter is a wonderful man,” Trump said — a sentence that has, it seems safe to assume, never before been uttered by a current or former American president. He prefaced this comment by asking whether anyone had seen the aforementioned movie. It would be safe to assume that perhaps Trump hadn’t, given his description of Lecter as “wonderful,” except that he then made reference to the final scene in the film, in which Lecter is about to murder someone. After mentioning that scene, Trump for some reason offered Lecter his congratulations.

One might justifiably wonder how this subject came up and why. The answer is uncomplicated in the way that Trump’s “sir” stories are.

Trump had just finished describing President Biden as a moron, worse than the 10 worst presidents in U.S. history combined.

“We’re supposed to cherish the office of president,” Trump said. “You don’t do what he did to try and win votes” — that is, serve as president as your predecessor racks up criminal indictments. (Trump frames this as proactive targeting by Biden, of course, but it isn’t.) Then Trump pivoted to his need to win back the White House in November.

“The biggest thing we have is we have millions of people here that are criminals,” he said. “We really — I mean, they’re criminals.”

“Send them back!” someone in the crowd shouted.

“Think of it: Venezuela just announced — and they had a new number was 67 now it’s 72 percent — 72 percent they’re down in crime because they took their gangs, their gang members, they took a lot of their criminals and they moved them into the United States of America,” Trump continued. “Jail populations all over the world are way down and these” — Trump searched for the best word for a moment — “ fools back there, the press, the fake news — they don’t want to report it.”

“You know why they’re down?” he continued. “Because they’re sending people in their jails into the United States. From Africa, from Asia, from all over the world. They’re emptying out their jails into the United States.”

The media isn’t reporting that crime in Venezuela is down 72 percent or that countries are emptying their jails into the United States because those things are not true, and we, unlike candidates for the presidency, are duty-bound to present information accurately.

The Venezuela thing was assessed by PolitiFact. The drop in crime was far smaller than Trump suggests because of several factors, including that the poor economy leaves less opportunity for criminals. There is no evidence that the government is sending criminals to the United States, and, in fact, most migration out of Venezuela is to nearby countries.

The idea that other countries, like those in Africa and Asia, are sending prison populations to the United States is more obviously baseless. How does that work, exactly? Not rhetorically, obviously; it’s clear how warnings about non-White people from exotic places are meant to land with the audience. But practically. Streams of 737s taking off from Lagos and landing in Tijuana?

It’s just an exaggeration, pushing the rhetoric further and further. If you accept that the media is lying to you and that there is evidence that Venezuela is shipping people north, then why not take it further? Why not believe, say, that China is building an army inside the United States?

Trump’s exaggerations had not yet peaked, of course.

“They’re emptying out their mental institutions into the United States, our beautiful country,” he continued. “And now the prison populations all over the world are down. They don’t want to report that. The mental institution population is down because they’re taking people from insane asylums and from mental institution — you know what the difference is, right? An insane asylum is a mental institution on steroids.”

Well, the difference really is that the former sounds scarier and more pejorative than the latter, so it has fallen out of favor. But scarier and pejorative is exactly what Trump is going for. And what better way to do that than to remind people of perhaps the scariest resident of a mental institution in American popular culture?

“‘Silence of the Lamb,’” Trump said. “Has anyone ever seen ‘The Silence of the Lambs’?”

And here we go.

“The late, great Hannibal Lecter is a wonderful man,” Trump continued. “He oftentimes would have a friend for dinner. Remember the last scene? ‘Excuse me, I’m about to have a friend for dinner’ as this poor doctor walked by. ‘I’m about to have a friend for dinner.’ But Hannibal Lecter, congratulations. The late, great Hannibal Lecter.”

And that was it. This was all off teleprompter, mind you, so there was no careful tying of the story back to the purported immigrant threat or to some evidence that, say, Thailand had sent the residents of a mental hospital to some swing state. Just a little riff on how scary this one guy from a movie is.

But Trump did put a fine point on the anecdote in the abstract.

“We have people that are being released into our country that we don’t want in our country,” Trump said, again using the baseless verb “released” to imply that it was part of some intentional effort. “And they’re coming in totally unchecked, totally unvetted, and we can’t let this happen. They’re just destroying our country.”

Once again, from the crowd: “Send them back!”

“And we’re sitting back,” Trump continued, “and we better damn well win this election ’cause if we don’t, our country is going to be doomed. It’s going to be doomed.”

It’s all apocalypticism. Everything is a slippery slope, and we’re all nearly at the bottom, all the time, in all ways. This is and has long been Trump’s pitch to voters, either that the United States is doomed because of the current president or (as was offered in 2020) that the collapse will occur imminently should he lose his position. The nuance comes only from how far Trump is willing to take it.

Praising Hannibal Lecter’s cannibalism is further than usual.

Election 2024

Get the latest news on the 2024 election from our reporters on the campaign trail and in Washington.

Who is running? President Biden and Donald Trump secured their parties’ nominations for the presidency . Here’s how we ended up with a Trump-Biden rematch again.

Key dates and events: From January to June, voters in all states and U.S. territories will pick their party’s nominee for president ahead of the summer conventions. Here are key dates and events on the 2024 election calendar .

Abortion and the election: Voters in about a dozen states could decide the fate of abortion rights with constitutional amendments on the ballot in a pivotal election year. Biden supports legal access to abortion , and he has encouraged Congress to pass a law that would codify abortion rights nationwide. After months of mixed signals about his position, Trump said the issue should be left to states . Here’s how Biden’s and Trump’s abortion stances have shifted over the years.

PHP Tutorial

Php advanced, mysql database, php examples, php reference, php operators.

Operators are used to perform operations on variables and values.

PHP divides the operators in the following groups:

• Arithmetic operators
• Assignment operators
• Comparison operators
• Increment/Decrement operators
• Logical operators
• String operators
• Array operators
• Conditional assignment operators

PHP Arithmetic Operators

The PHP arithmetic operators are used with numeric values to perform common arithmetical operations, such as addition, subtraction, multiplication etc.

PHP Assignment Operators

The PHP assignment operators are used with numeric values to write a value to a variable.

The basic assignment operator in PHP is "=". It means that the left operand gets set to the value of the assignment expression on the right.

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PHP Comparison Operators

The PHP comparison operators are used to compare two values (number or string):

PHP Increment / Decrement Operators

The PHP increment operators are used to increment a variable's value.

The PHP decrement operators are used to decrement a variable's value.

PHP Logical Operators

The PHP logical operators are used to combine conditional statements.

PHP String Operators

PHP has two operators that are specially designed for strings.

PHP Array Operators

The PHP array operators are used to compare arrays.

PHP Conditional Assignment Operators

The PHP conditional assignment operators are used to set a value depending on conditions:

PHP Exercises

Test yourself with exercises.

Multiply 10 with 5 , and output the result.

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• Health Department HAI/AR Programs
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Reference Antimicrobial Susceptibility Testing (AST) Data

At a glance.

Access downloadable distributions of minimum inhibitory concentration (MIC) for bacteria and fungi.

CDC programs perform AST of bacterial and bloodstream Candida isolates collected in surveillance programs and isolates submitted to CDC from the reference laboratories for susceptibility testing because of unusual resistance. CDC laboratories default method is broth microdilution using frozen in-house prepared panels according to standards established by the Clinical and Laboratory Standards Institute (CLSI Documents: M7 for bacteria; M27 with M60 for Candida ). Etest is a reference method for antifungal susceptibility to amphotericin B in accordance with CLSI M-27e4. CDC is making these data available online for use in setting breakpoints for interpretation of antimicrobial susceptibility testing.

The downloadable data contain tables and graphic representations that display minimum inhibitory concentration (MIC) distributions for various bacteria and Candida . We provide a description of the isolates tested with each dataset. CDC will continue to expand this database to include data from additional bacterial and fungal isolates and data from new antimicrobial drugs.

MIC data for Neisseria gonorrhoeae isolates can be found on the CDC Division of STD Prevention (DSTDP) Gonococcal Isolate Surveillance Project (GISP) Profiles and Annual Reports .

Downloadable Data & Additional Information

Distributions of mic for bacteria.

Acinetobacter

Coagulase-negative Staphylococci (CNS)

Enterobacteriaceae

Enterococcus

Pseudomonas

Staphylococcus aureus

Distributions of MIC for fungi

Additional information.

Description of AST data specifics

Reference AST Data: Supplementary Information

Supplemental information: interpretation rules for MIC values for bacterial pathogens

Lower range mic (mcg/ml), higher range mic (mcg/ml), not-determined mic.

If the MIC values are not available or not determined within the they will appear in the dataset as one of these:

• A blank cell
• A single period "."

If any of the above appear in the dataset, they should be interpreted as "not determined."

Clinical specimen terms

Terms that require decoding: BAL = Bronchoalveolar lavage

HAIs are associated with medical devices, complications following surgery, transmission between patients and healthcare workers, antibiotic overuse, and more.

For Everyone

Health care providers, public health.