How to get one element with each property value?

Question

1C-Bitrix

You need to get one element from the infoblock with each value of the specified property. How can I do that? I tried to do it with "arGroupBy" (CIBlockElement::getList), but in this case the resulting array contains only the number of elements for each property value, and there are no elements in it.

Answer 1

Few conditions, option if the selected element is in the "group" with the highest ID

use Bitrix\Main\Loader;
use Bitrix\Iblock\ElementTable;
use Bitrix\Iblock\ElementPropertyTable;
use Bitrix\Main\Entity\ExpressionField;

Loader::includeModule('iblock');

$iblockId = 1;
$propertyId = 1;

$elementIds = [];

$iterator = ElementPropertyTable::getList([
  'select' => [new ExpressionField('ID', 'MAX(%s)', 'IBLOCK_ELEMENT_ID'), 'VALUE'],
  'filter' => ['IBLOCK_PROPERTY_ID' => $propertyId, '!VALUE' => false],
]);

while($row = $iterator->fetch()) {
  $elementIds[] = $row['ID'];
}

$elements = ElementTable::getList([
  'select' => ['ID', 'NAME'],
  'filter' => ['IBLOCK_ID' => $iblockId, 'ID' => $elementIds],
])->fetchAll();

print_r($elements);