How to show duplicate data in multidimensional array using PHP - php

Question

I am using Spout Excel reader to read Excel files from php code and saving into a multidimensional array in PHP variable,Array looks like this
$array = [
[
'id[0]' => 'BX-78',
'Name[0]' => 'XXX',
'Address[0]' => 'YUUSATD'
],
[
'id[1]' => 'BX-79',
'Name[1]' => 'YYY',
'Address[1]' => 'DHJSHDJGY'
],
[
'id[2]' => 'BX-80',
'Name[2]' => 'ZZZ',
'Address[2]' => 'DDSDSDA'
]
[
'id[3]' => 'BX-78',
'Name[3]' => 'AAA',
'Address[3]' => 'FSDSDS'
][
'id[4]' => 'BX-81',
'Name[4]' => 'XXX',
'Address[4]' => 'DSDSDSD'
]];
Now i want to show duplicate data from above array using two keys ['id'] and ['name'] if id repeats show as duplicate data,
If name repeats show that row as duplicate data if both are duplicate show as again duplicate row
Otherwise it is unique row.
I have tried using multidimensional array sorting but it is using only one key to match data in rows.
foreach ($arrExcelData as $v) {
if (isset($arrExcelData[$v[0]])) {
// found duplicate
continue;
}
// remember unique item
$arrExcelData3[$v[0]] = $v;
}
// if you need a zero-based array, otheriwse work with $_data
$arrExcelData2 = array_values($arrExcelData3);
Edited : Expected Output Result :
Matching Rows:
Id Name Address
-------------------------
BX-78 XXX YUUSATD
BX-78 AAA DDSDSDA
BX-81 XXX DSDSDSD`

Answer 1

If you want to list the duplicate values, I think the address of the second match should be FSDSDS as there is not item with name AAA and value DDSDSDA:
BX-78 AAA FSDSDS
If that is the case, what you could do is to first use a double foreach to mark the arrays that contain a duplicate id or name by for example adding a property named id and name except when the array is itself in the second loop.
After this loop, you can tell which arrays are the duplicate ones. Instead of using a corresponding index 0 as in id[0], I have used reset and next so it is not tied to these indexes.
To get the filtered result you could use array_reduce to check for the array keys and unset them.
For example:
foreach ($array as $index => $a) {
foreach ($array as $v) {
if ($v === $a) continue;
if (reset($v) === reset($a)) $array[$index]["id"] = "duplicate";
if (next($v) === next($a)) $array[$index]["name"] = "duplicate";
}
}
$array = array_reduce($array, function($carry, $item) {
if (array_key_exists("id", $item) || array_key_exists("name", $item)) {
unset($item["id"], $item["name"]);
$carry[] = $item;
}
return $carry;
}, []);
print_r($array);
Result
Array
(
[0] => Array
(
[id[0]] => BX-78
[Name[0]] => XXX
[Address[0]] => YUUSATD
)
[1] => Array
(
[id[3]] => BX-78
[Name[3]] => AAA
[Address[3]] => FSDSDS
)
[2] => Array
(
[id[4]] => BX-81
[Name[4]] => XXX
[Address[4]] => DSDSDSD
)
)
See a php demo

Answer 2

I've this very pragmatic approach:
$spout_output = [
[
'id[0]' => 'BX-78',
'Name[0]' => 'XXX',
'Address[0]' => 'YUUSATD'
],
[
'id[1]' => 'BX-79',
'Name[1]' => 'YYY',
'Address[1]' => 'DHJSHDJGY'
],
[
'id[2]' => 'BX-80',
'Name[2]' => 'ZZZ',
'Address[2]' => 'DDSDSDA'
],
[
'id[3]' => 'BX-78',
'Name[3]' => 'AAA',
'Address[3]' => 'FSDSDS'
],
[
'id[4]' => 'BX-81',
'Name[4]' => 'XXX',
'Address[4]' => 'DSDSDSD'
]];
// store id to row, and name to row mappings.
// id and name will be keys, value will be an array of indexes of the array $spout_output
$id_to_rows = array();
$name_to_rows = array();
$duplicate_ids = array();
$duplicate_names = array();
foreach($spout_output as $row => $data)
{
$key_id = 'id['.$row.']';
$key_name = 'Name['.$row.']';
if(!isset($data[$key_id]))
continue;
$value_id = $data[$key_id];
$value_name = $data[$key_name];
if(!isset($id_to_rows[$value_id]))
{
$id_to_rows[$value_id] = array();
}
else
{
if(!isset($duplicate_ids[$value_id]))
{
$duplicate_ids[$value_id] = $id_to_rows[$value_id];
}
$duplicate_ids[$value_id][] = $row;
}
if(!isset($name_to_rows[$value_name]))
{
$name_to_rows[$value_name] = array();
}
else
{
if(!isset($duplicate_names[$value_name]))
{
$duplicate_names[$value_name] = $name_to_rows[$value_name];
}
$duplicate_names[$value_name][] = $row;
}
$id_to_rows[$value_id][] = $row;
$name_to_rows[$value_name][] = $row;
}
echo 'Duplicates:';
echo '<br>';
$shown_rows = array();
foreach($duplicate_ids as $id => $rows)
{
foreach($rows as $nr)
{
echo $id . '|' . $spout_output[$nr]['Name['.$nr.']'] . '|' . $spout_output[$nr]['Address['.$nr.']'];
echo '<br>';
$shown_rows[] = $nr;
}
}
foreach($duplicate_names as $name => $rows)
{
foreach($rows as $nr)
{
// if already shown above, skip this row
if(in_array($nr, $shown_rows))
continue;
echo $spout_output[$nr]['id['.$nr.']'] . '|' . $spout_output[$nr]['Name['.$nr.']'] . '|' . $spout_output[$nr]['Address['.$nr.']'];
echo '<br>';
$shown_rows[] = $nr;
}
}
Outputs:
Duplicates:
BX-78|XXX|YUUSATD
BX-78|AAA|FSDSDS
BX-81|XXX|DSDSDSD
I think your 'wanted output' contains an error in the address?
Anyway, with my code above I think you'll have enough mapped data to produce the output you want.

Answer 3

You could do something like this:
$dupes = [];
$current = [];
foreach ($array as $index => $entry) {
$idKey = "id[$index]";
$nameKey = "Name[$index]";
if (array_key_exists($entry[$idKey], $current)) {
$dupes[] = [$entry, $current[$entry[$idKey]]];
}
elseif (array_key_exists($entry[$nameKey], $current)) {
$dupes[] = [$entry, $current[$entry[$nameKey]]];
}
else {
$current[$entry[$idKey]] = $current[$entry[$nameKey]] = $entry;
}
}
print_r($dupes);
Which results in an array containing each set of duplicates (array of arrays):
Array
(
[0] => Array
(
[0] => Array
(
[id[3]] => BX-78
[Name[3]] => AAA
[Address[3]] => FSDSDS
)
[1] => Array
(
[id[0]] => BX-78
[Name[0]] => XXX
[Address[0]] => YUUSATD
)
)
[1] => Array
(
[0] => Array
(
[id[4]] => BX-81
[Name[4]] => XXX
[Address[4]] => DSDSDSD
)
[1] => Array
(
[id[0]] => BX-78
[Name[0]] => XXX
[Address[0]] => YUUSATD
)
)
)
Demo here: https://3v4l.org/JAtNU

Answer 4

In case someone of you are searching unique values by key.
function unique_multidim_array($array, $key) {
$temp_array = array();
$i = 0;
$key_array = array();
foreach($array as $val) {
if (!in_array($val[$key], $key_array)) {
$key_array[$i] = $val[$key];
$temp_array[$i] = $val;
}
$i++;
}
return $temp_array;
}
This function just takes multidimensional array and key value of field you need.
Then takes value of given array one by one (smaller arrays).
Then traverses given array and looking if taken key-value pair matches with given key.
After that if taken key-value pair matches with given key function just inserts smaller array in temporary array (array with unique values).
Don't forget to increment indexes of arrays ($i).
Then return array you got (with unique values) after function ends work.