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 = 375 
  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 = 375

Query time 0.00269

JSON explain

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    "nested_loop": [
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            "company",
            "lang_code",
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            "city",
            "state",
            "country",
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            "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",
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          },
          "used_columns": [
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            "company_description",
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            "subdomain_colors",
            "i18n_company",
            "i18n_address",
            "i18n_city"
          ]
        }
      },
      {
        "table": {
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          },
          "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",
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            "lang_code"
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          ],
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          "cost_info": {
            "read_cost": "0.89",
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            "prefix_cost": "0.99",
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          "used_columns": [
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            "path",
            "lang_code"
          ]
        }
      },
      {
        "table": {
          "table_name": "discussionA",
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          "possible_keys": [
            "object_id"
          ],
          "key": "object_id",
          "used_key_parts": [
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            "const"
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          "used_columns": [
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            "object_id",
            "object_type"
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      {
        "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"
          ],
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          "using_index": true,
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          },
          "used_columns": [
            "post_id",
            "thread_id",
            "status"
          ]
        }
      },
      {
        "table": {
          "table_name": "discussion_rating",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY",
            "thread_id"
          ],
          "key": "PRIMARY",
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          "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
375 en <p>Rivermist Creations is a quality handcrafted shop.&nbsp; We create lasting gifts, collectibles and keepsakes for all ages. We began making cloth baby dolls and have added several variations of those along with jointed plush animals, wood toys and home decor.&nbsp; We designed and create special magnetic pacifiers and parts needed to create magnetic baby bottles for use with not only our baby dolls but also any other doll with a magnetic mouth. We have recently added our own designed and printed fabrics for use in the swaddle dolls and clothing for the full body dolls. Our main priorities for our shop is Quality and Customer Service.&nbsp;</p> <p><strong><span style="color: inherit; font-family: inherit; font-size: 11.05px; font-weight: 600;">Return Accepted:&nbsp;Contact me within:&nbsp;</span><span class="text-gray-darker" style="color: inherit; font-family: inherit; font-weight: 600;">3 days of delivery -&nbsp;</span><span style="color: inherit; font-family: inherit; font-size: 11.05px; font-weight: 600;">ship items back within:&nbsp;</span></strong><span class="text-gray-darker" style="color: inherit; font-family: inherit; font-weight: 600;"><strong>7 days of delivery</strong></span><span style="color: inherit; font-family: inherit; font-weight: 600;"></span></p> <p>Buyer is responsible for return shipping.&nbsp;If the item is not returned in its original condition, the buyer is responsible for any loss in value.</p> <p>Due to the nature of these items, returns cannot be accepted for:</p> <ul><li>Custom or personalized orders</li><li>Items on sale</li></ul> {"tmenu_style":"H","default_colors":"N","link_color":"#674ea7","label_color":"#ae87c8","icon_color":"#351c75","main_btn_color":"#8e7cc3","branded_text_color":"#b4a7d6","vbp_1_url":"","vbp_2_url":"","vbp_3_url":"","vba_1_url":"","vba_2_url":"","vba_3_url":""} Rivermist Creations 717 E. French St. Stillwater A Rivermist Creations 717 E. French St. Stillwater OK US 74059 rivermistcreations@yahoo.com none Y 1586910849 617 a:4:{s:14:"company_fields";a:2:{i:37;s:5:"Nancy";i:38;s:5:"Allen";}s:15:"admin_firstname";s:5:"Nancy";s:14:"admin_lastname";s:5:"Allen";s:6:"fields";a:0:{}} 3 acct_1CGx5dG1WNxlimLZ 209028777624860 64011,168549,87530,171166,242747,165519,96736,255015,256139 UA-177073764-1 JCMZA88HM48ZW Handcrafted Quality Treasures https://www.facebook.com/RivermistCreations https://www.instagram.com/rivermistcreations/ https://www.pinterest.com/rivermistcreations <p><strong><span style="color: rgb(95, 73, 122);">Free Shipping on select items & when you spend $35 or more in Rivermist Creations</span></strong><br></p> <p><strong></strong></p> oauth.AdpfP6R3csB1GLCj5MieIpD-Gsu9cg_aEULqqNbp.pz9anAr4XQqAVu2B2T8G7TJcpcxtHJSHaoIiTczTdNE UA-177073764-1 209028777624860 rivermistcreations.com A N 0 0 0 0 0 S Professional Plan rivermistcreations 375_0