How to use array_multisort and array_column in PHP.

The Program

Here’s the complete code:

$arr = [

    ["name" => "birbal", "dept" => "HR"],

    ["name" => "arun", "dept" => "Production"],

    ["name" => "kamal", "dept" => "HR"],

    ["name" => "dev", "dept" => "Production"]

];

 

$name = array_column($arr, 'name');

$dept = array_column($arr, 'dept');

 

array_multisort($dept, SORT_ASC, $name, SORT_DESC, $arr);

 

print_r($arr);

Step-by-Step Explanation

1. Initializing the Multidimensional Array

$arr = [

    ["name" => "birbal", "dept" => "HR"],

    ["name" => "arun", "dept" => "Production"],

    ["name" => "kamal", "dept" => "HR"],

    ["name" => "dev", "dept" => "Production"]

];

This is a multidimensional array where each element is an associative array with two keys:

• name: Represents the name of an employee.
• dept: Represents the department of the employee.

2. Extracting Specific Columns Using array_column()

Syntax:

array_column(array $array, string|int $column_key): array

The array_column() function extracts values from a specific column in a multidimensional array and creates a one-dimensional array with those values.

Code:

$name = array_column($arr, 'name');

$dept = array_column($arr, 'dept');

• $name: Extracts the name column (["birbal", "arun", "kamal", "dev"]).
• $dept: Extracts the dept column (["HR", "Production", "HR", "Production"]).

3. Sorting the Array with array_multisort()

Syntax:

array_multisort(array &$array1, int $sort_order1, ..., array &$arrayN): bool

The array_multisort() function sorts multiple arrays or a multidimensional array based on one or more criteria. It updates the arrays in place and maintains the association between keys.

Code:

array_multisort($dept, SORT_ASC, $name, SORT_DESC, $arr);

Breakdown:

• $dept, SORT_ASC: Sort the dept column in ascending order (e.g., HR comes before Production).
• $name, SORT_DESC: For rows with the same department, sort the name column in descending order.
• $arr: Reorganize the original array ($arr) based on the sorting of $dept and $name.

4. Printing the Sorted Array

Code:

print_r($arr);

The print_r() function prints human-readable information about an array. After sorting, the output will look like this:

Array

(

    [0] => Array

        (

            [name] => kamal

            [dept] => HR

        )

 

    [1] => Array

        (

            [name] => birbal

            [dept] => HR

        )

 

    [2] => Array

        (

            [name] => dev

            [dept] => Production

        )

 

    [3] => Array

        (

            [name] => arun

            [dept] => Production

        )

)

Key Takeaways

1.      array_column(): Simplifies extracting specific columns from a multidimensional array, making the data easier to manipulate.

2.   array_multisort(): Enables advanced sorting of arrays by multiple criteria, ideal for structured datasets.

3.   Sorting Logic:

o   First by dept in ascending order.

o   Then by name in descending order.

Practical Applications

• Sorting employee data by departments and names.
• Organizing product inventories by categories and subcategories.
• Simplifying data preparation for APIs and reports.

By understanding and utilizing these PHP functions, you can handle complex sorting scenarios efficiently. Experiment with the program and adapt it to your specific use cases!