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 = 250 
WHERE 
  cscart_products_categories.product_id IN (
    1572, 1574, 1592, 4974, 2399, 1576, 1665, 
    1586, 5277, 1593, 5899, 5640, 2201, 
    5934, 5939, 3929, 5918, 1562, 5284, 
    5376, 4193, 1571, 5287, 3226, 5281, 
    3218, 5397, 4995, 5270, 2393, 3464, 
    1575, 5278, 5187, 5549, 3935, 1588, 
    1563, 1570, 3826
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00380

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "189.86"
    },
    "grouping_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "range",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "pt",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "rows_examined_per_scan": 220,
            "rows_produced_per_join": 220,
            "filtered": "100.00",
            "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`cscart_products_categories`.`product_id` in (1572,1574,1592,4974,2399,1576,1665,1586,5277,1593,5899,5640,2201,5934,5939,3929,5918,1562,5284,5376,4193,1571,5287,3226,5281,3218,5397,4995,5270,2393,3464,1575,5278,5187,5549,3935,1588,1563,1570,3826))",
            "cost_info": {
              "read_cost": "87.01",
              "eval_cost": "22.00",
              "prefix_cost": "109.01",
              "data_read_per_join": "3K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ]
          }
        },
        {
          "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": [
              "softwarepirmam_hewadelivard_cscart_4.cscart_products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 11,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "55.00",
              "eval_cost": "1.10",
              "prefix_cost": "186.01",
              "data_read_per_join": "34K"
            },
            "used_columns": [
              "category_id",
              "storefront_id",
              "usergroup_ids",
              "status"
            ],
            "attached_condition": "((`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`storefront_id` in (0,1)) and ((`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`usergroup_ids`))) and (`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`status` in ('A','H')))"
          }
        },
        {
          "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",
              "softwarepirmam_hewadelivard_cscart_4.cscart_products_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 11,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "2.75",
              "eval_cost": "1.10",
              "prefix_cost": "189.86",
              "data_read_per_join": "176"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}