Remove duplicate items from an array [duplicate]

The array_unique function will do this for you. You just needed to add the SORT_REGULAR flag:

$items_thread = array_unique($items_thread, SORT_REGULAR);

However, as bren suggests, you should do this in SQL if possible.

You'd be much better off filtering out the duplicates in the SQL query. add a constraint which fetches a UNIQUE recipientID

To remove duplicate values then we can use array_unique() function. The functionality of it is to accept an array and returns another array without duplicate values.

General description of array_unique() is given below:

General Format = array array_unique(array $array [, int $sort_flags=sort_string] )
Parameters     = array: Input array ->sort_flags:
    The second optional parameter is used to compare items as follows
         1. SORT_REGULAR - Normal
         2. SORT_NUMERIC - Numerically
         3. SORT_STRING - As
         4. string  SORT_LOCALE_STRING - As string, based on the current locale.
Return Value   = Another array without duplicate values 

Example 1:

<?php
$array=array('cricket'=>11,'football'=>11,'chess'=>2);
echo"<br/><b>Initially the values of \$array is:</b><br/>";
var_dump($array);
echo"<br/><b>After removing the duplicates:</b><br/>";
print_r(array_unique($array));
?>

Output:

Initially the values of $array is:
array(3) {
  ["cricket"] => int(11)
  ["football"] => int(11)
  ["chess"] => int(2)
}

After removing the duplicates:
Array
(
    [cricket] => 11
    [chess] => 2
)