why getting "array_map(): Argument #2 should be an array" error while running complex query?

When working with complex database queries in PHP, you may encounter the error "array_map(): Argument #2 should be an array" when attempting to use the array_map() function.

The array_map() function takes two arguments: a callback function and an array. The callback function is applied to each element of the array, and the results are returned as a new array.

In the provided code, the second argument to array_map() is $results, which is the result of a database query. However, $results is not an array; it's a query object. To fix this error, you need to convert the query object to an array before passing it to array_map().

There are two ways to convert a query object to an array:

1. Use the toArray() method.
2. Use the get() method.

The toArray() method returns an array of associative arrays, where each associative array represents a row of the query result. The get() method returns an array of objects, where each object represents a row of the query result.

In the provided code, you can use the toArray() method to convert the query object to an array:

```

$queryResults = $results->whereBetween('l.received', [$start, $end])
    ->groupBy('l.disposition')         
    ->orderBy('l.disposition')
    ->get()->toArray();
$count = count($results);
if($count > 0)
{
 $results = array_map(function ($value) {
            return (array)$value;
        }, $results); 

Or you can use the get() method:

```

$queryResults->whereBetween('l.received', [$start, $end])
    ->groupBy('l.disposition')         
    ->orderBy('l.disposition')
    ->get()->toArray();
$count = count($results);
if($count > 0)
{
 $results = array_map(function ($value) {
            return (array)$value;
        },$queryResults);

In both cases, the $queryResults variable will be an array, which you can then pass to the array_map() function.

By converting the query object to an array before passing it to array_map(), you can avoid the "array_map(): Argument #2 should be an array" error and successfully apply the callback function to each element of the array.