Query time 0.00062
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 (8501,8503,8504,8506,8507,8508,8509,8510,8511,8512,8514,8515,8516,8517,8518,8519,8521,8477,8476,8474,8377,8376,8375,8374,8368,8367,8272,8271,8270,8269,8268,8267)) 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 |
8267 |
|
D |
4437 |
8268 |
|
D |
4438 |
8269 |
|
D |
4439 |
8270 |
|
D |
4440 |
8271 |
|
D |
4441 |
8272 |
|
D |
4445 |
8367 |
|
D |
4446 |
8368 |
|
D |
4250 |
8374 |
|
D |
4447 |
8375 |
|
D |
4448 |
8376 |
|
D |
4449 |
8377 |
|
D |
4260 |
8474 |
|
D |
4450 |
8476 |
|
D |
4451 |
8477 |
|
D |
4452 |
8501 |
|
D |
4464 |
8503 |
|
D |
4465 |
8504 |
|
D |
4466 |
8506 |
|
D |
4467 |
8507 |
|
D |
4468 |
8508 |
|
D |
4469 |
8509 |
|
D |
4770 |
8510 |
|
D |
4470 |
8511 |
|
D |
4471 |
8512 |
|
D |
4472 |
8514 |
|
D |
4474 |
8515 |
|
D |
4475 |
8516 |
|
D |
4476 |
8517 |
|
D |
4477 |
8518 |
|
D |
4478 |
8519 |
|
D |
4479 |
8521 |
|
D |
4480 |