SELECT 
  products_categories.product_id, 
  GROUP_CONCAT(
    IF(
      products_categories.link_type = "M", 
      CONCAT(
        products_categories.category_id, 
        "M"
      ), 
      products_categories.category_id
    )
  ) AS category_ids, 
  product_position_source.position AS position 
FROM 
  products_categories 
  INNER JOIN categories ON categories.category_id = products_categories.category_id 
  AND categories.storefront_id IN (0, 1) 
  AND (
    categories.usergroup_ids = '' 
    OR FIND_IN_SET(0, categories.usergroup_ids) 
    OR FIND_IN_SET(1, categories.usergroup_ids)
  ) 
  AND categories.status IN ('A', 'H') 
  LEFT JOIN products_categories AS product_position_source ON products_categories.product_id = product_position_source.product_id 
  AND product_position_source.category_id = 22116 
WHERE 
  products_categories.product_id IN (
    296840, 296925, 296815, 296844, 296874, 
    296922, 296924, 296843, 296902, 296891, 
    296863, 296923, 296850, 296916, 296813, 
    296856, 296854, 296901, 296878, 296871, 
    296867, 296879, 296918, 296870, 296855, 
    296866, 296896, 296812, 296865, 296898, 
    296877, 296920, 296889, 296921, 296926, 
    296849, 296814, 296859, 296873, 296839, 
    296893, 296841, 296919, 296881, 296861, 
    296883, 296838, 296853, 296899, 296846, 
    296858, 296894, 296869, 296892, 296845, 
    296895, 296864, 296917, 296851, 296862, 
    296882, 296900, 296875, 296876, 296906, 
    296860, 296868, 296857, 296842
  ) 
GROUP BY 
  products_categories.product_id

Query time 0.00244

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "247.90"
    },
    "grouping_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "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": 275,
            "rows_produced_per_join": 275,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "27.90",
              "eval_cost": "27.50",
              "prefix_cost": "55.40",
              "data_read_per_join": "4K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`goimagine`.`products_categories`.`product_id` in (296840,296925,296815,296844,296874,296922,296924,296843,296902,296891,296863,296923,296850,296916,296813,296856,296854,296901,296878,296871,296867,296879,296918,296870,296855,296866,296896,296812,296865,296898,296877,296920,296889,296921,296926,296849,296814,296859,296873,296839,296893,296841,296919,296881,296861,296883,296838,296853,296899,296846,296858,296894,296869,296892,296845,296895,296864,296917,296851,296862,296882,296900,296875,296876,296906,296860,296868,296857,296842))"
          }
        },
        {
          "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",
              "goimagine.products_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 275,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "68.75",
              "eval_cost": "27.50",
              "prefix_cost": "151.65",
              "data_read_per_join": "4K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        },
        {
          "table": {
            "table_name": "categories",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "goimagine.products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 13,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "68.75",
              "eval_cost": "1.38",
              "prefix_cost": "247.90",
              "data_read_per_join": "35K"
            },
            "used_columns": [
              "category_id",
              "usergroup_ids",
              "status",
              "storefront_id"
            ],
            "attached_condition": "((`goimagine`.`categories`.`storefront_id` in (0,1)) and ((`goimagine`.`categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`goimagine`.`categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`goimagine`.`categories`.`usergroup_ids`))) and (`goimagine`.`categories`.`status` in ('A','H')))"
          }
        }
      ]
    }
  }
}