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 $dbSections = Bitrix\Iblock\SectionTable::getList([
    'select' => ['ID', 'INNER_ID' => 'INNER_SECTION.ID'],
    'filter' => [
        'IBLOCK_ID' => ***,
        'ID' => ***
    ],
    'runtime' => [
        'INNER_SECTION' => [
            'data_type' => Bitrix\Iblock\SectionTable::class,
            'reference' => [
                '<this.LEFT_MARGIN' => 'ref.LEFT_MARGIN',
                '>this.RIGHT_MARGIN' => 'ref.RIGHT_MARGIN',
                'this.IBLOCK_ID' => 'ref.IBLOCK_ID'
            ],
            'join_type' => 'LEFT'
        ]
    ]
]);