Query time 0.00069
JSON explain
{
"query_block": {
"select_id": 1,
"cost_info": {
"query_cost": "230.41"
},
"grouping_operation": {
"using_filesort": false,
"nested_loop": [
{
"table": {
"table_name": "q_discussion",
"access_type": "range",
"possible_keys": [
"object_id"
],
"key": "object_id",
"used_key_parts": [
"object_id",
"object_type"
],
"key_length": "6",
"rows_examined_per_scan": 32,
"rows_produced_per_join": 32,
"filtered": "100.00",
"index_condition": "((`portal`.`q_discussion`.`object_id` in (32689,32690,32691,32692,32693,32694,32695,32696,32697,32698,32699,32700,32701,32702,32703,32704,32705,32706,32707,32708,32709,32710,32711,32712,32713,32714,32715,32716,32717,32718,32719,32720)) and (`portal`.`q_discussion`.`object_type` = 'P'))",
"cost_info": {
"read_cost": "70.41",
"eval_cost": "6.40",
"prefix_cost": "76.81",
"data_read_per_join": "512"
},
"used_columns": [
"thread_id",
"object_id",
"object_type",
"type"
]
}
},
{
"table": {
"table_name": "q_discussion_posts",
"access_type": "ref",
"possible_keys": [
"thread_id",
"thread_id_2"
],
"key": "thread_id",
"used_key_parts": [
"thread_id"
],
"key_length": "3",
"ref": [
"portal.q_discussion.thread_id"
],
"rows_examined_per_scan": 2,
"rows_produced_per_join": 64,
"filtered": "100.00",
"cost_info": {
"read_cost": "64.00",
"eval_cost": "12.80",
"prefix_cost": "153.61",
"data_read_per_join": "28K"
},
"used_columns": [
"post_id",
"thread_id",
"status"
],
"attached_condition": "<if>(is_not_null_compl(q_discussion_posts), (`portal`.`q_discussion_posts`.`status` = 'A'), true)"
}
},
{
"table": {
"table_name": "q_discussion_rating",
"access_type": "eq_ref",
"possible_keys": [
"PRIMARY",
"thread_id"
],
"key": "PRIMARY",
"used_key_parts": [
"post_id"
],
"key_length": "3",
"ref": [
"portal.q_discussion_posts.post_id"
],
"rows_examined_per_scan": 1,
"rows_produced_per_join": 64,
"filtered": "100.00",
"cost_info": {
"read_cost": "64.00",
"eval_cost": "12.80",
"prefix_cost": "230.41",
"data_read_per_join": "1024"
},
"used_columns": [
"rating_value",
"post_id",
"thread_id"
],
"attached_condition": "<if>(is_not_null_compl(q_discussion_rating), ((`portal`.`q_discussion_rating`.`thread_id` = `portal`.`q_discussion`.`thread_id`) and (`portal`.`q_discussion_rating`.`rating_value` <> 0)), true)"
}
}
]
}
}
}
Result
product_id |
average_rating |
discussion_type |
discussion_thread_id |
32689 |
|
B |
21535 |
32690 |
|
B |
21534 |
32691 |
|
B |
21532 |
32692 |
|
B |
21531 |
32693 |
|
B |
21529 |
32694 |
|
B |
21528 |
32695 |
|
B |
21527 |
32696 |
|
B |
21525 |
32697 |
|
B |
21524 |
32698 |
|
B |
21523 |
32699 |
|
B |
21522 |
32700 |
|
B |
21521 |
32701 |
|
B |
21520 |
32702 |
|
B |
21518 |
32703 |
|
B |
21517 |
32704 |
|
B |
21515 |
32705 |
|
B |
21514 |
32706 |
|
B |
21513 |
32707 |
|
B |
21511 |
32708 |
|
B |
21510 |
32709 |
|
B |
21509 |
32710 |
|
B |
21507 |
32711 |
|
B |
21646 |
32712 |
|
B |
21642 |
32713 |
|
B |
21623 |
32714 |
|
B |
21625 |
32715 |
|
B |
21626 |
32716 |
|
B |
21628 |
32717 |
|
B |
21630 |
32718 |
|
B |
21638 |
32719 |
|
B |
21621 |
32720 |
|
B |
21584 |