Is it more efficient to use array_column to extract objects in PHP than to use foreach loops? What are the specific performance differences?

M66 2025-05-11

In PHP, there are many ways to process arrays, where array_column and foreach loops are two common methods for extracting specific values or object properties in an array. Although these two methods are often used to implement similar functions, they differ in performance. So, is array_column more efficient than foreach ? In this article, we will analyze the performance differences and applicable scenarios in detail.

1. Basic usage of array_column and foreach

1.1 Use array_column to extract object properties

The array_column function is a very useful function built into PHP, which extracts the values of a specified column from a multidimensional array, suitable for extracting specific properties of an object from an array of objects. For example, suppose we have the following array of objects:

 $objects = [
    (object) ['id' => 1, 'name' => 'Alice'],
    (object) ['id' => 2, 'name' => 'Bob'],
    (object) ['id' => 3, 'name' => 'Charlie']
];

// use array_column Extract all 'name' property
$names = array_column($objects, 'name');
print_r($names);

The output will be:

 Array
(
    [0] => Alice
    [1] => Bob
    [2] => Charlie
)

array_column receives two parameters, the first is the array, and the second is the field name that needs to be extracted. Its internal implementation is very efficient, especially when handling large arrays, enabling column data to be extracted more quickly.

1.2 Use foreach to loop to extract object properties

Another common way is to manually iterate through the array using a foreach loop and extract the property values of each object. For example:

 $objects = [
    (object) ['id' => 1, 'name' => 'Alice'],
    (object) ['id' => 2, 'name' => 'Bob'],
    (object) ['id' => 3, 'name' => 'Charlie']
];

$names = [];
foreach ($objects as $object) {
    $names[] = $object->name;
}
print_r($names);

The output result is the same as array_column :

 Array
(
    [0] => Alice
    [1] => Bob
    [2] => Charlie
)

The foreach loop requires manual logic to extract the attribute values of each object. The code is usually longer, but it also has good flexibility.

2. Performance differences

2.1 Performance advantages of array_column

array_column is a function implemented internally in PHP and written in C, so it is usually more efficient than foreach when dealing with large-scale arrays. This is because array_column is optimized for specific scenarios. It directly extracts specified columns in the array at the bottom and avoids loop control and array assignment operations at the PHP code level.

2.2 Performance disadvantages of foreach loops

In contrast, a foreach loop requires manual traversal of the array and processed one by one. Although this method is flexible, each loop requires multiple PHP operations, such as array operations, conditional judgment, etc. Therefore, when dealing with very large arrays, the foreach loop may not perform as well as array_column .

3. Specific performance comparison

Suppose we have an array of 10000 objects, we will use array_column and foreach to extract the object's name attributes and test their execution time.

 // Create a Container 10000 Array of objects
$objects = [];
for ($i = 0; $i < 10000; $i++) {
    $objects[] = (object) ['id' => $i, 'name' => 'Name ' . $i];
}

// test array_column performance
$startTime = microtime(true);
$names = array_column($objects, 'name');
$endTime = microtime(true);
echo "array_column execution time: " . ($endTime - $startTime) . " seconds\n";

// test foreach 循环performance
$startTime = microtime(true);
$names = [];
foreach ($objects as $object) {
    $names[] = $object->name;
}
$endTime = microtime(true);
echo "foreach execution time: " . ($endTime - $startTime) . " seconds\n";

In tests, array_column will usually execute shorter than foreach , especially when the array is larger.

4. Conclusion

In PHP, the array_column function is usually more efficient than the foreach loop, especially when it is necessary to extract specific columns from large-scale arrays. array_column utilizes PHP internal optimization to quickly extract data with lower overhead, while foreach loops require more PHP operations, resulting in poor performance.

However, foreach loops still have some advantages in some scenarios where more customization logic is required, especially when you need to perform additional operations while traversing the array. In actual development, if you simply extract a column in an array, it is recommended to use array_column first.

I hope this article can help you better understand the performance differences between these two methods and make more appropriate choices.

array_column