SELECT 
  SQL_CALC_FOUND_ROWS (
    CASE WHEN products.parent_product_id <> 0 THEN products.parent_product_id ELSE products.product_id END
  ) AS product_id, 
  descr1.product as product, 
  companies.company as company_name, 
  MIN(
    IF(
      prices.percentage_discount = 0, 
      prices.price, 
      prices.price - (
        prices.price * prices.percentage_discount
      )/ 100
    )
  ) as price, 
  GROUP_CONCAT(
    products.product_id 
    ORDER BY 
      products.parent_product_id ASC, 
      products.product_id ASC
  ) AS product_ids, 
  GROUP_CONCAT(
    products.product_type 
    ORDER BY 
      products.parent_product_id ASC, 
      products.product_id ASC
  ) AS product_types, 
  GROUP_CONCAT(
    products.parent_product_id 
    ORDER BY 
      products.parent_product_id ASC, 
      products.product_id ASC
  ) AS parent_product_ids, 
  products.product_type, 
  products.parent_product_id, 
  descr1.full_description as full_description 
FROM 
  cscart_products as products 
  LEFT JOIN cscart_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'en' 
  LEFT JOIN cscart_product_prices as prices ON prices.product_id = products.product_id 
  AND prices.lower_limit = 1 
  LEFT JOIN cscart_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 cscart_companies AS companies ON companies.company_id = products.company_id 
  INNER JOIN cscart_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN cscart_categories ON cscart_categories.category_id = products_categories.category_id 
  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') 
  AND cscart_categories.storefront_id IN (0, 1) 
WHERE 
  1 
  AND products.product_id NOT IN (241) 
  AND companies.status IN ('A') 
  AND prices.price >= 474.05 
  AND prices.price <= 523.95 
  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.company_id IN('1', '2', '3', '4', '5', '6') 
  AND products.product_type != 'D' 
GROUP BY 
  product_id 
ORDER BY 
  product asc, 
  products.product_id ASC 
LIMIT 
  0, 3

Query time 0.00753

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "44.30"
    },
    "ordering_operation": {
      "using_filesort": true,
      "grouping_operation": {
        "using_temporary_table": true,
        "using_filesort": true,
        "buffer_result": {
          "using_temporary_table": true,
          "nested_loop": [
            {
              "table": {
                "table_name": "companies",
                "access_type": "ALL",
                "possible_keys": [
                  "PRIMARY"
                ],
                "rows_examined_per_scan": 6,
                "rows_produced_per_join": 1,
                "filtered": "16.67",
                "cost_info": {
                  "read_cost": "3.27",
                  "eval_cost": "0.20",
                  "prefix_cost": "3.47",
                  "data_read_per_join": "7K"
                },
                "used_columns": [
                  "company_id",
                  "status",
                  "company"
                ],
                "attached_condition": "((`atulecarter_atul_demo1`.`companies`.`status` = 'A') and (`atulecarter_atul_demo1`.`companies`.`company_id` in ('1','2','3','4','5','6')))"
              }
            },
            {
              "table": {
                "table_name": "cscart_categories",
                "access_type": "ALL",
                "possible_keys": [
                  "PRIMARY",
                  "c_status",
                  "p_category_id"
                ],
                "rows_examined_per_scan": 86,
                "rows_produced_per_join": 3,
                "filtered": "4.00",
                "using_join_buffer": "Block Nested Loop",
                "cost_info": {
                  "read_cost": "20.01",
                  "eval_cost": "0.69",
                  "prefix_cost": "24.16",
                  "data_read_per_join": "8K"
                },
                "used_columns": [
                  "category_id",
                  "storefront_id",
                  "usergroup_ids",
                  "status"
                ],
                "attached_condition": "(((`atulecarter_atul_demo1`.`cscart_categories`.`usergroup_ids` = '') or find_in_set(0,`atulecarter_atul_demo1`.`cscart_categories`.`usergroup_ids`) or find_in_set(1,`atulecarter_atul_demo1`.`cscart_categories`.`usergroup_ids`)) and (`atulecarter_atul_demo1`.`cscart_categories`.`status` in ('A','H')) and (`atulecarter_atul_demo1`.`cscart_categories`.`storefront_id` in (0,1)))"
              }
            },
            {
              "table": {
                "table_name": "products_categories",
                "access_type": "ref",
                "possible_keys": [
                  "PRIMARY",
                  "pt"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "category_id"
                ],
                "key_length": "3",
                "ref": [
                  "atulecarter_atul_demo1.cscart_categories.category_id"
                ],
                "rows_examined_per_scan": 3,
                "rows_produced_per_join": 10,
                "filtered": "100.00",
                "using_index": true,
                "cost_info": {
                  "read_cost": "3.63",
                  "eval_cost": "2.06",
                  "prefix_cost": "29.85",
                  "data_read_per_join": "165"
                },
                "used_columns": [
                  "product_id",
                  "category_id"
                ],
                "attached_condition": "(`atulecarter_atul_demo1`.`products_categories`.`product_id` <> 241)"
              }
            },
            {
              "table": {
                "table_name": "products",
                "access_type": "eq_ref",
                "possible_keys": [
                  "PRIMARY",
                  "status"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "product_id"
                ],
                "key_length": "3",
                "ref": [
                  "atulecarter_atul_demo1.products_categories.product_id"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 0,
                "filtered": "5.00",
                "cost_info": {
                  "read_cost": "10.32",
                  "eval_cost": "0.10",
                  "prefix_cost": "42.24",
                  "data_read_per_join": "2K"
                },
                "used_columns": [
                  "product_id",
                  "product_type",
                  "status",
                  "company_id",
                  "usergroup_ids",
                  "parent_product_id"
                ],
                "attached_condition": "((`atulecarter_atul_demo1`.`products`.`company_id` = `atulecarter_atul_demo1`.`companies`.`company_id`) and ((`atulecarter_atul_demo1`.`products`.`usergroup_ids` = '') or find_in_set(0,`atulecarter_atul_demo1`.`products`.`usergroup_ids`) or find_in_set(1,`atulecarter_atul_demo1`.`products`.`usergroup_ids`)) and (`atulecarter_atul_demo1`.`products`.`status` = 'A') and (`atulecarter_atul_demo1`.`products`.`product_type` <> 'D'))"
              }
            },
            {
              "table": {
                "table_name": "prices",
                "access_type": "ref",
                "possible_keys": [
                  "usergroup",
                  "product_id",
                  "lower_limit",
                  "usergroup_id"
                ],
                "key": "usergroup",
                "used_key_parts": [
                  "product_id"
                ],
                "key_length": "3",
                "ref": [
                  "atulecarter_atul_demo1.products_categories.product_id"
                ],
                "rows_examined_per_scan": 3,
                "rows_produced_per_join": 0,
                "filtered": "3.26",
                "index_condition": "((`atulecarter_atul_demo1`.`prices`.`lower_limit` = 1) and (`atulecarter_atul_demo1`.`prices`.`usergroup_id` in (0,0,1)))",
                "cost_info": {
                  "read_cost": "1.56",
                  "eval_cost": "0.01",
                  "prefix_cost": "44.10",
                  "data_read_per_join": "1"
                },
                "used_columns": [
                  "product_id",
                  "price",
                  "percentage_discount",
                  "lower_limit",
                  "usergroup_id"
                ],
                "attached_condition": "((`atulecarter_atul_demo1`.`prices`.`price` >= 474.05) and (`atulecarter_atul_demo1`.`prices`.`price` <= 523.95))"
              }
            },
            {
              "table": {
                "table_name": "prices_2",
                "access_type": "ref",
                "possible_keys": [
                  "usergroup",
                  "product_id",
                  "lower_limit",
                  "usergroup_id"
                ],
                "key": "usergroup",
                "used_key_parts": [
                  "product_id"
                ],
                "key_length": "3",
                "ref": [
                  "atulecarter_atul_demo1.products_categories.product_id"
                ],
                "rows_examined_per_scan": 3,
                "rows_produced_per_join": 0,
                "filtered": "9.74",
                "not_exists": true,
                "cost_info": {
                  "read_cost": "0.15",
                  "eval_cost": "0.00",
                  "prefix_cost": "44.29",
                  "data_read_per_join": "0"
                },
                "used_columns": [
                  "product_id",
                  "price",
                  "lower_limit",
                  "usergroup_id"
                ],
                "attached_condition": "(<if>(found_match(prices_2), isnull(`atulecarter_atul_demo1`.`prices_2`.`price`), true) and <if>(is_not_null_compl(prices_2), ((`atulecarter_atul_demo1`.`prices_2`.`lower_limit` = 1) and (`atulecarter_atul_demo1`.`prices_2`.`price` < `atulecarter_atul_demo1`.`prices`.`price`) and (`atulecarter_atul_demo1`.`prices_2`.`usergroup_id` in (0,0,1))), true))"
              }
            },
            {
              "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": [
                  "atulecarter_atul_demo1.products_categories.product_id",
                  "const"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 0,
                "filtered": "100.00",
                "cost_info": {
                  "read_cost": "0.01",
                  "eval_cost": "0.00",
                  "prefix_cost": "44.30",
                  "data_read_per_join": "68"
                },
                "used_columns": [
                  "product_id",
                  "lang_code",
                  "product",
                  "full_description"
                ]
              }
            }
          ]
        }
      }
    }
  }
}

Result

product_id product company_name price product_ids product_types parent_product_ids product_type parent_product_id full_description
238 Apple iPhone 4S Black CS-Cart 499.99000000 238 P 0 P 0 <p> 16GB iPhone 4S locked AT&amp;T model. Will work on AT&amp;T. Now you can use your voice to use your iPhone. Just talk to Siri as you would to a person: "Do I need an umbrella?" or "Any great burgers around here?" or "Where's the closest ATM?" Siri not only understands what you say, it knows what you mean.1 It figures out the right apps to use to find the right answer. Then, just like a personal assistant, it answers you. Siri makes phone calls, sends messages, schedules meetings, sets reminders, and more. How much more? Just ask, and Siri tells you that, too. Two cores in the A5 chip deliver up to two times more power and up to seven times faster graphics.2 And you'll feel the effects. Fast. iPhone 4S is quick and responsive, which makes all the difference when you're launching apps, browsing the web, gaming, and doing just about everything. And no matter what you're doing, you can keep on doing it. Because the A5 chip is so power-efficient, iPhone 4S has outstanding battery life. This just might be the best camera ever on a phone. And with all-new optics, it just might be the only camera you need. Because behind every shot, you've got 8-megapixel resolution and a custom lens with a larger f/2.4 aperture. Not to mention an improved backside illumination sensor, excellent auto white balance, advanced color accuracy, face detection, and reduced motion blur. It all means that no matter how many people, how much light, and how much action you capture, everything looks exactly as it should. And just wait until you see the photos. Shoot stunning 1080p HD video everywhere you go. With all-new optics, the light is always right, the color is always vivid, and everything will look even better than you remember. Video stabilization steadies shaky shots. And you can edit video right on iPhone and share your lush life as fast as you shoot. </p>
239 Apple iPhone 4S White CS-Cart 509.99000000 239 P 0 P 0 <p> 16GB iPhone 4S locked AT&amp;T model. Will work on AT&amp;T. Now you can use your voice to use your iPhone. Just talk to Siri as you would to a person: "Do I need an umbrella?" or "Any great burgers around here?" or "Where's the closest ATM?" Siri not only understands what you say, it knows what you mean.1 It figures out the right apps to use to find the right answer. Then, just like a personal assistant, it answers you. Siri makes phone calls, sends messages, schedules meetings, sets reminders, and more. How much more? Just ask, and Siri tells you that, too. Two cores in the A5 chip deliver up to two times more power and up to seven times faster graphics.2 And you'll feel the effects. Fast. iPhone 4S is quick and responsive, which makes all the difference when you're launching apps, browsing the web, gaming, and doing just about everything. And no matter what you're doing, you can keep on doing it. Because the A5 chip is so power-efficient, iPhone 4S has outstanding battery life. This just might be the best camera ever on a phone. And with all-new optics, it just might be the only camera you need. Because behind every shot, you've got 8-megapixel resolution and a custom lens with a larger f/2.4 aperture. Not to mention an improved backside illumination sensor, excellent auto white balance, advanced color accuracy, face detection, and reduced motion blur. It all means that no matter how many people, how much light, and how much action you capture, everything looks exactly as it should. And just wait until you see the photos. Shoot stunning 1080p HD video everywhere you go. With all-new optics, the light is always right, the color is always vivid, and everything will look even better than you remember. Video stabilization steadies shaky shots. And you can edit video right on iPhone and share your lush life as fast as you shoot. </p>
240 Apple® - iPad® with Retina® display Wi-Fi - 64GB - Black CS-Cart 499.00000000 240 P 0 P 0 <p> iPad features a stunning Retina display, iSight® and FaceTime cameras, the all new A6X chip and ultrafast wireless. And with access to over 275,000 apps1 on the App Store, you can do more than ever. </p>