SELECT 
  cscart_products_categories.product_id, 
  GROUP_CONCAT(
    IF(
      cscart_products_categories.link_type = "M", 
      CONCAT(
        cscart_products_categories.category_id, 
        "M"
      ), 
      cscart_products_categories.category_id
    )
  ) AS category_ids, 
  product_position_source.position AS position 
FROM 
  cscart_products_categories 
  INNER JOIN cscart_categories ON cscart_categories.category_id = cscart_products_categories.category_id 
  AND cscart_categories.storefront_id IN (0, 1) 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  LEFT JOIN cscart_products_categories AS product_position_source ON cscart_products_categories.product_id = product_position_source.product_id 
  AND product_position_source.category_id = 7165 
WHERE 
  cscart_products_categories.product_id IN (
    82488, 91886, 91887, 92329, 92330, 92331, 
    92332, 91479, 92000, 91538, 91539, 
    90210, 90233, 91536, 91537, 90190, 
    92346, 91901, 91902, 91903, 92345, 
    92347, 92348, 90182, 90172, 85638, 
    82551, 90276, 85637, 85636, 90204, 
    90215, 85635, 90209, 90232, 85583, 
    92342, 90196, 91897, 91898, 91899, 
    92341, 92343, 92344, 88925, 88926, 
    88927, 91470
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.01676

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "82.19"
    },
    "grouping_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "range",
            "possible_keys": [
              "PRIMARY",
              "link_type",
              "pt"
            ],
            "key": "pt",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "rows_examined_per_scan": 91,
            "rows_produced_per_join": 91,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "9.39",
              "eval_cost": "9.10",
              "prefix_cost": "18.49",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (82488,91886,91887,92329,92330,92331,92332,91479,92000,91538,91539,90210,90233,91536,91537,90190,92346,91901,91902,91903,92345,92347,92348,90182,90172,85638,82551,90276,85637,85636,90204,90215,85635,90209,90232,85583,92342,90196,91897,91898,91899,92341,92343,92344,88925,88926,88927,91470))"
          }
        },
        {
          "table": {
            "table_name": "product_position_source",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id",
              "product_id"
            ],
            "key_length": "6",
            "ref": [
              "const",
              "nuie_scalesta_net.cscart_products_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 91,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "22.75",
              "eval_cost": "9.10",
              "prefix_cost": "50.34",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        },
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "nuie_scalesta_net.cscart_products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 4,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "22.75",
              "eval_cost": "0.46",
              "prefix_cost": "82.19",
              "data_read_per_join": "11K"
            },
            "used_columns": [
              "category_id",
              "usergroup_ids",
              "status",
              "storefront_id"
            ],
            "attached_condition": "((`nuie_scalesta_net`.`cscart_categories`.`storefront_id` in (0,1)) and ((`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`))) and (`nuie_scalesta_net`.`cscart_categories`.`status` in ('A','H')))"
          }
        }
      ]
    }
  }
}