SELECT 
  company_descriptions.*, 
  companies.*, 
  vendor_plan_descriptions.plan, 
  seo_names.name as seo_name, 
  seo_names.path as seo_path, 
  vendor_ga_tracking_code, 
  vendor_fb_tracking_code, 
  AVG(discussion_rating.rating_value) AS average_rating, 
  CONCAT(
    companies.company_id, 
    '_', 
    IF (
      discussion_rating.thread_id, discussion_rating.thread_id, 
      '0'
    )
  ) AS company_thread_ids 
FROM 
  companies AS companies 
  LEFT JOIN company_descriptions AS company_descriptions ON company_descriptions.company_id = companies.company_id 
  AND company_descriptions.lang_code = 'en' 
  LEFT JOIN vendor_plan_descriptions ON companies.plan_id = vendor_plan_descriptions.plan_id 
  AND vendor_plan_descriptions.lang_code = 'en' 
  LEFT JOIN seo_names ON seo_names.object_id = 6478 
  AND seo_names.type = 'm' 
  AND seo_names.dispatch = '' 
  AND seo_names.lang_code = 'en' 
  LEFT JOIN discussion as discussionA ON discussionA.object_id = companies.company_id 
  AND discussionA.object_type = 'M' 
  LEFT JOIN discussion_posts ON discussion_posts.thread_id = discussionA.thread_id 
  AND discussion_posts.status = 'A' 
  LEFT JOIN discussion_rating ON discussionA.thread_id = discussion_rating.thread_id 
  AND discussion_rating.post_id = discussion_posts.post_id 
WHERE 
  companies.company_id = 6478

Query time 0.00238

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "2.87"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "companies",
          "access_type": "const",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "company_id"
          ],
          "key_length": "4",
          "ref": [
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.00",
            "eval_cost": "0.10",
            "prefix_cost": "0.00",
            "data_read_per_join": "14K"
          },
          "used_columns": [
            "company_id",
            "status",
            "company",
            "lang_code",
            "address",
            "city",
            "state",
            "country",
            "zipcode",
            "email",
            "phone",
            "url",
            "storefront",
            "secure_storefront",
            "entry_page",
            "redirect_customer",
            "countries_list",
            "timestamp",
            "shippings",
            "logos",
            "request_user_id",
            "request_account_name",
            "request_account_data",
            "plan_id",
            "stripe_connect_account_id",
            "identifier_facebook_pixel",
            "featured_products",
            "sd_ga_tracking_code",
            "paypal_commerce_platform_account_id",
            "tagline",
            "url_facebook",
            "url_instagram",
            "url_twitter",
            "url_pinterest",
            "announcement",
            "shippo_api_token",
            "shippo_carrier",
            "shippo_service_type",
            "vendor_ga_tracking_code",
            "vendor_fb_tracking_code",
            "custom_domain",
            "custom_domain_status",
            "taxjar_key",
            "taxjar_export_statuses",
            "taxjar_export_csv_data",
            "ag_hide_city",
            "updated_timestamp",
            "suspend_date",
            "grace_period_start",
            "last_time_suspended",
            "last_debt_notification_time",
            "tax_number",
            "stripe_connect_account_type",
            "registered_from_storefront_id"
          ]
        }
      },
      {
        "table": {
          "table_name": "company_descriptions",
          "access_type": "const",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "company_id",
            "lang_code"
          ],
          "key_length": "10",
          "ref": [
            "const",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.00",
            "eval_cost": "0.10",
            "prefix_cost": "0.00",
            "data_read_per_join": "1K"
          },
          "used_columns": [
            "company_id",
            "lang_code",
            "company_description",
            "terms",
            "subdomain_colors",
            "i18n_company",
            "i18n_address",
            "i18n_city"
          ]
        }
      },
      {
        "table": {
          "table_name": "vendor_plan_descriptions",
          "access_type": "const",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "plan_id",
            "lang_code"
          ],
          "key_length": "10",
          "ref": [
            "const",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.00",
            "eval_cost": "0.10",
            "prefix_cost": "0.00",
            "data_read_per_join": "1K"
          },
          "used_columns": [
            "plan_id",
            "lang_code",
            "plan"
          ]
        }
      },
      {
        "table": {
          "table_name": "seo_names",
          "access_type": "ref",
          "possible_keys": [
            "PRIMARY",
            "dispatch"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "object_id",
            "type",
            "dispatch",
            "lang_code"
          ],
          "key_length": "206",
          "ref": [
            "const",
            "const",
            "const",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.88",
            "eval_cost": "0.10",
            "prefix_cost": "0.98",
            "data_read_per_join": "1K"
          },
          "used_columns": [
            "name",
            "object_id",
            "type",
            "dispatch",
            "path",
            "lang_code"
          ]
        }
      },
      {
        "table": {
          "table_name": "discussionA",
          "access_type": "const",
          "possible_keys": [
            "object_id"
          ],
          "key": "object_id",
          "used_key_parts": [
            "object_id",
            "object_type"
          ],
          "key_length": "6",
          "ref": [
            "const",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "using_index": true,
          "cost_info": {
            "read_cost": "0.75",
            "eval_cost": "0.10",
            "prefix_cost": "1.83",
            "data_read_per_join": "24"
          },
          "used_columns": [
            "thread_id",
            "object_id",
            "object_type"
          ]
        }
      },
      {
        "table": {
          "table_name": "discussion_posts",
          "access_type": "ref",
          "possible_keys": [
            "thread_id",
            "thread_id_2"
          ],
          "key": "thread_id_2",
          "used_key_parts": [
            "thread_id",
            "status"
          ],
          "key_length": "6",
          "ref": [
            "goimagine.discussionA.thread_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "using_index": true,
          "cost_info": {
            "read_cost": "0.25",
            "eval_cost": "0.18",
            "prefix_cost": "2.25",
            "data_read_per_join": "787"
          },
          "used_columns": [
            "post_id",
            "thread_id",
            "status"
          ]
        }
      },
      {
        "table": {
          "table_name": "discussion_rating",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY",
            "thread_id"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "post_id"
          ],
          "key_length": "3",
          "ref": [
            "goimagine.discussion_posts.post_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.44",
            "eval_cost": "0.18",
            "prefix_cost": "2.87",
            "data_read_per_join": "28"
          },
          "used_columns": [
            "rating_value",
            "post_id",
            "thread_id"
          ],
          "attached_condition": "<if>(is_not_null_compl(discussion_rating), (`goimagine`.`discussion_rating`.`thread_id` = `goimagine`.`discussionA`.`thread_id`), true)"
        }
      }
    ]
  }
}

Result

company_id lang_code company_description terms subdomain_colors i18n_company i18n_address i18n_city status company address city state country zipcode email phone url storefront secure_storefront entry_page redirect_customer countries_list timestamp shippings logos request_user_id request_account_name request_account_data plan_id stripe_connect_account_id identifier_facebook_pixel featured_products sd_ga_tracking_code paypal_commerce_platform_account_id tagline url_facebook url_instagram url_twitter url_pinterest announcement shippo_api_token shippo_carrier shippo_service_type vendor_ga_tracking_code vendor_fb_tracking_code custom_domain custom_domain_status taxjar_key taxjar_export_statuses taxjar_export_csv_data ag_hide_city updated_timestamp suspend_date grace_period_start last_time_suspended last_debt_notification_time tax_number stripe_connect_account_type registered_from_storefront_id plan seo_name seo_path average_rating company_thread_ids
6478 en <p>I grew up in San Diego, California and I've been drawing and painting since the moment I could pick up a crayon. Fine art and the ocean were my first loves. I became obsessed with ancient Egyptian antiquity at a very young age after poking through one of my Dad's college art history books and that led me to try and duplicate the photos I saw in the books with pencils and crayons. Hence, my interest in creating and appreciating art began and blossomed. I tend to think outside the box and try to do things different than everyone else does, much to the dismay of my parents, lol. I welcome you to explore all the categories of my shop, as anything you see can be custom ordered in the theme, colors and style that you would prefer. Thank you for visiting and for supporting my small business. Happy shopping!</p> {"tmenu_style":"V","default_colors":"N","link_color":"#007d89","label_color":"#00a0af","icon_color":"#00a0af","main_btn_color":"#6dd1d6","branded_text_color":"#00a0af","vbp_1_url":"","vbp_2_url":"","vbp_3_url":"","vba_1_url":"","vba_2_url":"","vba_3_url":""} BellaBenĂ´it Studios 1819 Sunny Ridge Rd, Apt 104 NAMPA A BellaBenĂ´it Studios 1819 Sunny Ridge Rd, Apt 104 NAMPA ID US 83686 BellaBenoitStudios@gmail.com +12082845964 none Y 1650654155 0 3 acct_1KswGGAtNg9xhCKw QF2WP2FMADFAY All art, all the time...Fine art, three dimensional resin art, embroidery of my actual art work and handmade dolls, clothes and dollhouse miniatures. https://www.facebook.com/artistLisaB https://www.instagram.com/bellabenoit_studios/ oauth.5KHYx03fZZCO6vioizCPSA5KYtSBKe89VruFPlVJ.FthOhSBqA0LsHW-e_3PC5PcfiXeJB21NOCHqi2ZaWuM A N 0 0 0 0 0 S Professional Plan bellabenoitstudios 6478_0