What is the issue with creating a function in PHP where not all fields are required to be filled?

When creating a function in PHP where not all fields are required to be filled, the issue arises when trying to access optional parameters that were not provided. To solve this, you can use default parameter values in the function declaration. By setting default values for optional parameters, you ensure that the function can still be called without providing all arguments.

function exampleFunction($requiredParam, $optionalParam = null) {
    // Function logic here
}