It is pretty simple to delete duplicate values from PHP Array. But sometimes we confuse for how can we remove. But PHP provide pre-define function array_unique that can help to remove duplicate values from Array.
array_unique() through we can get only unique value from array. So, you can see bellow example i have 34 value two times but when i use array_unique() then it will return only unique value as bellow output:
$myArray = [11,34,56,78,34];
$myArrayNew = array_unique($myArray);
 => 11
 => 34
 => 56
 => 78