SELECT 
  jmj_companies.company_id, 
  jmj_companies.lang_code, 
  jmj_companies.email, 
  jmj_companies.timestamp, 
  jmj_companies.status, 
  company_descr.i18n_company as company, 
  jmj_companies.tax_number, 
  jmj_company_descriptions.company_description, 
  absolute_rating.rating AS absolute_vendor_rating, 
  jmj_vendor_plan_descriptions.plan, 
  AVG(
    jmj_discussion_rating.rating_value
  ) AS average_rating, 
  CONCAT(
    jmj_companies.company_id, 
    '_', 
    IF (
      jmj_discussion_rating.thread_id, 
      jmj_discussion_rating.thread_id, 
      '0'
    )
  ) AS company_thread_ids, 
  jmj_companies.suspend_date, 
  jmj_companies.last_time_suspended 
FROM 
  jmj_companies 
  LEFT JOIN jmj_company_descriptions as company_descr ON company_descr.company_id = jmj_companies.company_id 
  AND company_descr.lang_code = 'en' 
  LEFT JOIN jmj_company_descriptions ON jmj_company_descriptions.company_id = jmj_companies.company_id 
  AND jmj_company_descriptions.lang_code = 'en' 
  LEFT JOIN jmj_absolute_rating AS absolute_rating ON absolute_rating.object_id = jmj_companies.company_id 
  AND absolute_rating.object_type = 'company' 
  LEFT JOIN jmj_vendor_plan_descriptions ON jmj_companies.plan_id = jmj_vendor_plan_descriptions.plan_id 
  AND jmj_vendor_plan_descriptions.lang_code = 'en' 
  LEFT JOIN jmj_discussion ON jmj_discussion.object_id = jmj_companies.company_id 
  AND jmj_discussion.object_type = 'M' 
  LEFT JOIN jmj_discussion_posts ON jmj_discussion_posts.thread_id = jmj_discussion.thread_id 
  AND jmj_discussion_posts.status = 'A' 
  LEFT JOIN jmj_discussion_rating ON jmj_discussion.thread_id = jmj_discussion_rating.thread_id 
  AND jmj_discussion_rating.post_id = jmj_discussion_posts.post_id 
WHERE 
  1 
  AND jmj_companies.status = 'A' 
GROUP BY 
  company_thread_ids 
ORDER BY 
  company_descr.i18n_company desc 
LIMIT 
  0, 10

Query time 0.01102

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "68.55"
    },
    "ordering_operation": {
      "using_filesort": true,
      "grouping_operation": {
        "using_temporary_table": true,
        "using_filesort": false,
        "nested_loop": [
          {
            "table": {
              "table_name": "jmj_companies",
              "access_type": "ALL",
              "rows_examined_per_scan": 35,
              "rows_produced_per_join": 3,
              "filtered": "10.00",
              "cost_info": {
                "read_cost": "11.30",
                "eval_cost": "0.70",
                "prefix_cost": "12.00",
                "data_read_per_join": "37K"
              },
              "used_columns": [
                "company_id",
                "status",
                "lang_code",
                "email",
                "timestamp",
                "plan_id",
                "suspend_date",
                "last_time_suspended",
                "tax_number"
              ],
              "attached_condition": "(`jmj_test`.`jmj_companies`.`status` = 'A')"
            }
          },
          {
            "table": {
              "table_name": "company_descr",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "company_id",
                "lang_code"
              ],
              "key_length": "10",
              "ref": [
                "jmj_test.jmj_companies.company_id",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 3,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "3.50",
                "eval_cost": "0.70",
                "prefix_cost": "16.20",
                "data_read_per_join": "6K"
              },
              "used_columns": [
                "company_id",
                "lang_code",
                "i18n_company"
              ]
            }
          },
          {
            "table": {
              "table_name": "jmj_company_descriptions",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "company_id",
                "lang_code"
              ],
              "key_length": "10",
              "ref": [
                "jmj_test.jmj_companies.company_id",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 3,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "3.50",
                "eval_cost": "0.70",
                "prefix_cost": "20.40",
                "data_read_per_join": "6K"
              },
              "used_columns": [
                "company_id",
                "lang_code",
                "company_description"
              ]
            }
          },
          {
            "table": {
              "table_name": "absolute_rating",
              "access_type": "ALL",
              "possible_keys": [
                "PRIMARY"
              ],
              "rows_examined_per_scan": 2,
              "rows_produced_per_join": 7,
              "filtered": "100.00",
              "using_join_buffer": "Block Nested Loop",
              "cost_info": {
                "read_cost": "2.02",
                "eval_cost": "1.40",
                "prefix_cost": "23.82",
                "data_read_per_join": "784"
              },
              "used_columns": [
                "object_id",
                "object_type",
                "rating"
              ],
              "attached_condition": "<if>(is_not_null_compl(absolute_rating), ((`jmj_test`.`absolute_rating`.`object_id` = `jmj_test`.`jmj_companies`.`company_id`) and (`jmj_test`.`absolute_rating`.`object_type` = 'company')), true)"
            }
          },
          {
            "table": {
              "table_name": "jmj_vendor_plan_descriptions",
              "access_type": "ALL",
              "possible_keys": [
                "PRIMARY"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 7,
              "filtered": "100.00",
              "using_join_buffer": "Block Nested Loop",
              "cost_info": {
                "read_cost": "2.03",
                "eval_cost": "1.40",
                "prefix_cost": "27.25",
                "data_read_per_join": "5K"
              },
              "used_columns": [
                "plan_id",
                "lang_code",
                "plan"
              ],
              "attached_condition": "<if>(is_not_null_compl(jmj_vendor_plan_descriptions), ((`jmj_test`.`jmj_vendor_plan_descriptions`.`plan_id` = `jmj_test`.`jmj_companies`.`plan_id`) and (`jmj_test`.`jmj_vendor_plan_descriptions`.`lang_code` = 'en')), true)"
            }
          },
          {
            "table": {
              "table_name": "jmj_discussion",
              "access_type": "eq_ref",
              "possible_keys": [
                "object_id"
              ],
              "key": "object_id",
              "used_key_parts": [
                "object_id",
                "object_type"
              ],
              "key_length": "6",
              "ref": [
                "jmj_test.jmj_companies.company_id",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 7,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "3.50",
                "eval_cost": "1.40",
                "prefix_cost": "32.15",
                "data_read_per_join": "168"
              },
              "used_columns": [
                "thread_id",
                "object_id",
                "object_type"
              ],
              "attached_condition": "<if>(is_not_null_compl(jmj_discussion), (`jmj_test`.`jmj_discussion`.`object_id` = `jmj_test`.`jmj_companies`.`company_id`), true)"
            }
          },
          {
            "table": {
              "table_name": "jmj_discussion_posts",
              "access_type": "ref",
              "possible_keys": [
                "thread_id",
                "thread_id_2"
              ],
              "key": "thread_id",
              "used_key_parts": [
                "thread_id"
              ],
              "key_length": "3",
              "ref": [
                "jmj_test.jmj_discussion.thread_id"
              ],
              "rows_examined_per_scan": 3,
              "rows_produced_per_join": 21,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "17.50",
                "eval_cost": "4.20",
                "prefix_cost": "53.85",
                "data_read_per_join": "9K"
              },
              "used_columns": [
                "post_id",
                "thread_id",
                "status"
              ],
              "attached_condition": "<if>(is_not_null_compl(jmj_discussion_posts), (`jmj_test`.`jmj_discussion_posts`.`status` = 'A'), true)"
            }
          },
          {
            "table": {
              "table_name": "jmj_discussion_rating",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "thread_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "post_id"
              ],
              "key_length": "3",
              "ref": [
                "jmj_test.jmj_discussion_posts.post_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 21,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "10.50",
                "eval_cost": "4.20",
                "prefix_cost": "68.55",
                "data_read_per_join": "336"
              },
              "used_columns": [
                "rating_value",
                "post_id",
                "thread_id"
              ],
              "attached_condition": "<if>(is_not_null_compl(jmj_discussion_rating), (`jmj_test`.`jmj_discussion_rating`.`thread_id` = `jmj_test`.`jmj_discussion`.`thread_id`), true)"
            }
          }
        ]
      }
    }
  }
}