SELECT 
  SQL_CALC_FOUND_ROWS products.product_id, 
  descr1.product as product, 
  companies.company as company_name, 
  popularity.total as popularity, 
  MIN(
    IF(
      prices.percentage_discount = 0, 
      prices.price, 
      prices.price - (
        prices.price * prices.percentage_discount
      )/ 100
    )
  ) as price, 
  absolute_rating.rating AS absolute_vendor_rating, 
  products.product_type, 
  products.parent_product_id, 
  products.list_price as list_price, 
  MAX(
    100 - (
      (prices.price * 100) / products.list_price
    )
  ) AS sales_discount 
FROM 
  ushop_products as products 
  LEFT JOIN ushop_product_features_values ON ushop_product_features_values.product_id = products.product_id 
  AND ushop_product_features_values.lang_code = 'es' 
  LEFT JOIN ushop_product_features ON ushop_product_features_values.feature_id = ushop_product_features.feature_id 
  LEFT JOIN ushop_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'es' 
  LEFT JOIN ushop_product_prices as prices ON prices.product_id = products.product_id 
  AND prices.lower_limit = 1 
  LEFT JOIN ushop_product_prices as prices_2 ON prices.product_id = prices_2.product_id 
  AND prices_2.lower_limit = 1 
  AND prices_2.price < prices.price 
  AND prices_2.usergroup_id IN (0, 0, 1) 
  LEFT JOIN ushop_companies AS companies ON companies.company_id = products.company_id 
  INNER JOIN ushop_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN ushop_categories ON ushop_categories.category_id = products_categories.category_id 
  AND (
    ushop_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, ushop_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, ushop_categories.usergroup_ids
    )
  ) 
  AND ushop_categories.status IN ('A', 'H') 
  AND ushop_categories.storefront_id IN (0, 1) 
  LEFT JOIN ushop_product_popularity as popularity ON popularity.product_id = products.product_id 
  LEFT JOIN ushop_absolute_rating AS absolute_rating ON absolute_rating.object_id = products.company_id 
  AND absolute_rating.object_type = 'company' 
  LEFT JOIN ushop_product_sales ON ushop_product_sales.product_id = products.product_id 
  AND ushop_product_sales.category_id = products_categories.category_id 
  LEFT JOIN ushop_cp_auctions as auctions ON products.product_id = auctions.product_id 
  LEFT JOIN ushop_users ON products.company_id = ushop_users.company_id 
  AND ushop_users.user_type = 'V' 
  AND ushop_users.user_id = 0 
WHERE 
  1 
  AND companies.status IN ('A') 
  AND (
    products.usergroup_ids = '' 
    OR FIND_IN_SET(0, products.usergroup_ids) 
    OR FIND_IN_SET(1, products.usergroup_ids)
  ) 
  AND products.status IN ('A') 
  AND prices.usergroup_id IN (0, 0, 1) 
  AND prices_2.price IS NULL 
  AND products.parent_product_id = 0 
  AND (
    CASE WHEN (
      products.cp_active_auction_id > 0
    ) THEN (
      (
        auctions.users = '' 
        OR FIND_IN_SET(0, auctions.users)
      ) 
      AND auctions.show_on_category = 'Y'
    ) ELSE 1 END 
    OR ushop_users.company_id = products.company_id
  ) 
  AND products.product_type <> 'W' 
  AND products.product_type != 'D' 
GROUP BY 
  products.product_id 
HAVING 
  sales_discount > 0 
  AND price < list_price 
ORDER BY 
  sales_discount desc, 
  products.product_id ASC 
LIMIT 
  0, 18

Query time 0.00938

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "53.05"
    },
    "ordering_operation": {
      "using_filesort": true,
      "grouping_operation": {
        "using_temporary_table": true,
        "using_filesort": false,
        "nested_loop": [
          {
            "table": {
              "table_name": "companies",
              "access_type": "ALL",
              "possible_keys": [
                "PRIMARY"
              ],
              "rows_examined_per_scan": 7,
              "rows_produced_per_join": 0,
              "filtered": "14.29",
              "cost_info": {
                "read_cost": "1.17",
                "eval_cost": "0.10",
                "prefix_cost": "1.27",
                "data_read_per_join": "6K"
              },
              "used_columns": [
                "company_id",
                "status",
                "company"
              ],
              "attached_condition": "(`marketplace`.`companies`.`status` = 'A')"
            }
          },
          {
            "table": {
              "table_name": "products",
              "access_type": "ALL",
              "possible_keys": [
                "PRIMARY",
                "status",
                "idx_parent_product_id"
              ],
              "rows_examined_per_scan": 251,
              "rows_produced_per_join": 19,
              "filtered": "7.81",
              "using_join_buffer": "hash join",
              "cost_info": {
                "read_cost": "10.12",
                "eval_cost": "1.96",
                "prefix_cost": "30.99",
                "data_read_per_join": "83K"
              },
              "used_columns": [
                "product_id",
                "product_type",
                "status",
                "company_id",
                "list_price",
                "usergroup_ids",
                "parent_product_id",
                "cp_active_auction_id"
              ],
              "attached_condition": "((`marketplace`.`products`.`company_id` = `marketplace`.`companies`.`company_id`) and (`marketplace`.`products`.`parent_product_id` = 0) and ((`marketplace`.`products`.`usergroup_ids` = '') or (0 <> find_in_set(0,`marketplace`.`products`.`usergroup_ids`)) or (0 <> find_in_set(1,`marketplace`.`products`.`usergroup_ids`))) and (`marketplace`.`products`.`status` = 'A') and (`marketplace`.`products`.`product_type` <> 'W') and (`marketplace`.`products`.`product_type` <> 'D'))"
            }
          },
          {
            "table": {
              "table_name": "prices",
              "access_type": "ref",
              "possible_keys": [
                "usergroup",
                "product_id",
                "lower_limit",
                "usergroup_id"
              ],
              "key": "product_id",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "marketplace.products.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 19,
              "filtered": "98.81",
              "cost_info": {
                "read_cost": "4.90",
                "eval_cost": "1.94",
                "prefix_cost": "37.85",
                "data_read_per_join": "464"
              },
              "used_columns": [
                "product_id",
                "price",
                "percentage_discount",
                "lower_limit",
                "usergroup_id"
              ],
              "attached_condition": "((`marketplace`.`prices`.`lower_limit` = 1) and (`marketplace`.`prices`.`usergroup_id` in (0,0,1)))"
            }
          },
          {
            "table": {
              "table_name": "products_categories",
              "access_type": "ref",
              "possible_keys": [
                "PRIMARY",
                "pt"
              ],
              "key": "pt",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "marketplace.products.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 19,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "4.84",
                "eval_cost": "1.94",
                "prefix_cost": "44.63",
                "data_read_per_join": "309"
              },
              "used_columns": [
                "product_id",
                "category_id"
              ]
            }
          },
          {
            "table": {
              "table_name": "prices_2",
              "access_type": "ref",
              "possible_keys": [
                "usergroup",
                "product_id",
                "lower_limit",
                "usergroup_id"
              ],
              "key": "product_id",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "marketplace.products.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 1,
              "filtered": "9.88",
              "not_exists": true,
              "cost_info": {
                "read_cost": "4.84",
                "eval_cost": "0.19",
                "prefix_cost": "51.41",
                "data_read_per_join": "45"
              },
              "used_columns": [
                "product_id",
                "price",
                "lower_limit",
                "usergroup_id"
              ],
              "attached_condition": "(<if>(found_match(prices_2), (`marketplace`.`prices_2`.`price` is null), true) and <if>(is_not_null_compl(prices_2), ((`marketplace`.`prices_2`.`lower_limit` = 1) and (`marketplace`.`prices_2`.`price` < `marketplace`.`prices`.`price`) and (`marketplace`.`prices_2`.`usergroup_id` in (0,0,1))), true))"
            }
          },
          {
            "table": {
              "table_name": "popularity",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "total"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "marketplace.products.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 1,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.48",
                "eval_cost": "0.19",
                "prefix_cost": "52.08",
                "data_read_per_join": "61"
              },
              "used_columns": [
                "product_id",
                "total"
              ]
            }
          },
          {
            "table": {
              "table_name": "ushop_categories",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "c_status",
                "p_category_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "category_id"
              ],
              "key_length": "3",
              "ref": [
                "marketplace.products_categories.category_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "5.00",
              "cost_info": {
                "read_cost": "0.48",
                "eval_cost": "0.01",
                "prefix_cost": "52.75",
                "data_read_per_join": "316"
              },
              "used_columns": [
                "category_id",
                "storefront_id",
                "usergroup_ids",
                "status"
              ],
              "attached_condition": "(((`marketplace`.`ushop_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`marketplace`.`ushop_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`marketplace`.`ushop_categories`.`usergroup_ids`))) and (`marketplace`.`ushop_categories`.`status` in ('A','H')) and (`marketplace`.`ushop_categories`.`storefront_id` in (0,1)))"
            }
          },
          {
            "table": {
              "table_name": "absolute_rating",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "object_id",
                "object_type"
              ],
              "key_length": "102",
              "ref": [
                "marketplace.companies.company_id",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.00",
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                "prefix_cost": "52.76",
                "data_read_per_join": "10"
              },
              "used_columns": [
                "object_id",
                "object_type",
                "rating"
              ]
            }
          },
          {
            "table": {
              "table_name": "ushop_product_sales",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "pa"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "category_id",
                "product_id"
              ],
              "key_length": "6",
              "ref": [
                "marketplace.products_categories.category_id",
                "marketplace.products.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "using_index": true,
              "cost_info": {
                "read_cost": "0.02",
                "eval_cost": "0.01",
                "prefix_cost": "52.80",
                "data_read_per_join": "1"
              },
              "used_columns": [
                "category_id",
                "product_id"
              ]
            }
          },
          {
            "table": {
              "table_name": "auctions",
              "access_type": "ref",
              "possible_keys": [
                "product_id"
              ],
              "key": "product_id",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "4",
              "ref": [
                "marketplace.products.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "index_condition": "<if>(is_not_null_compl(auctions), (`marketplace`.`products`.`product_id` = `marketplace`.`auctions`.`product_id`), true)",
              "cost_info": {
                "read_cost": "0.02",
                "eval_cost": "0.01",
                "prefix_cost": "52.83",
                "data_read_per_join": "19"
              },
              "used_columns": [
                "product_id",
                "users",
                "show_on_category"
              ]
            }
          },
          {
            "table": {
              "table_name": "ushop_users",
              "access_type": "const",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "user_id"
              ],
              "key_length": "3",
              "ref": [
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.00",
                "eval_cost": "0.01",
                "prefix_cost": "52.84",
                "data_read_per_join": "630"
              },
              "used_columns": [
                "user_id",
                "user_type",
                "company_id"
              ],
              "attached_condition": "(<if>(found_match(ushop_users), ((0 <> (case when (`marketplace`.`products`.`cp_active_auction_id` > 0) then (((`marketplace`.`auctions`.`users` = '') or (0 <> find_in_set(0,`marketplace`.`auctions`.`users`))) and (`marketplace`.`auctions`.`show_on_category` = 'Y')) else 1 end)) or (`marketplace`.`ushop_users`.`company_id` = `marketplace`.`companies`.`company_id`)), true) and <if>(is_not_null_compl(ushop_users), ((`marketplace`.`ushop_users`.`company_id` = `marketplace`.`companies`.`company_id`) and (`marketplace`.`ushop_users`.`user_type` = 'V')), true))"
            }
          },
          {
            "table": {
              "table_name": "ushop_product_features_values",
              "access_type": "ref",
              "possible_keys": [
                "lang_code",
                "product_id",
                "idx_product_feature_variant_id"
              ],
              "key": "idx_product_feature_variant_id",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "marketplace.products.product_id"
              ],
              "rows_examined_per_scan": 3,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "using_index": true,
              "cost_info": {
                "read_cost": "0.03",
                "eval_cost": "0.03",
                "prefix_cost": "52.90",
                "data_read_per_join": "227"
              },
              "used_columns": [
                "feature_id",
                "product_id",
                "lang_code"
              ],
              "attached_condition": "<if>(is_not_null_compl(ushop_product_features_values), (`marketplace`.`ushop_product_features_values`.`lang_code` = 'es'), true)"
            }
          },
          {
            "table": {
              "table_name": "ushop_product_features",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "feature_id"
              ],
              "key_length": "3",
              "ref": [
                "marketplace.ushop_product_features_values.feature_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "using_index": true,
              "cost_info": {
                "read_cost": "0.07",
                "eval_cost": "0.03",
                "prefix_cost": "53.00",
                "data_read_per_join": "128"
              },
              "used_columns": [
                "feature_id"
              ]
            }
          },
          {
            "table": {
              "table_name": "descr1",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "product_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "product_id",
                "lang_code"
              ],
              "key_length": "9",
              "ref": [
                "marketplace.products.product_id",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.02",
                "eval_cost": "0.03",
                "prefix_cost": "53.05",
                "data_read_per_join": "1K"
              },
              "used_columns": [
                "product_id",
                "lang_code",
                "product"
              ]
            }
          }
        ]
      }
    }
  }
}