How to count equal records in a single column and get that same number?

With php5.5 you can combine the array_column() function to extract the index values and return them as a new array, using the array_count_values() function that says how many equal values there are in the array, the keys are the values of the database and the values are the number of occurrences.

$arr = [['str' => 'abc'], ['str' => 2015], ['str' => 2015], ['str' => 'doge'], ['str' => 'wow'], ['str' => 'wow']];
$itens = array_count_values(array_column($arr, 'str'));

echo "<pre>";
print_r($itens);

Return:

Array
(
    [abc] => 1
    [2015] => 2
    [doge] => 1
    [wow] => 2
)