Query time 0.00075
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 (32622,32623,32624,32625,32626,32627,32628,32629,32630,32631,32632,32633,32634,32635,32636,32637,32638,32639,32640,32641,32642,32643,32644,32645,32646,32647,32648,32649,32650,32651,32652,32653)) 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 |
32622 |
|
B |
21181 |
32623 |
|
B |
21182 |
32624 |
|
B |
21183 |
32625 |
|
B |
21184 |
32626 |
|
B |
21185 |
32627 |
|
B |
21186 |
32628 |
|
B |
21187 |
32629 |
|
B |
21189 |
32630 |
|
B |
21191 |
32631 |
|
B |
21193 |
32632 |
|
B |
21195 |
32633 |
|
B |
21196 |
32634 |
|
B |
21197 |
32635 |
|
B |
21198 |
32636 |
|
B |
21199 |
32637 |
|
B |
21426 |
32638 |
|
B |
21201 |
32639 |
|
B |
21202 |
32640 |
|
B |
21203 |
32641 |
|
B |
21205 |
32642 |
|
B |
21429 |
32643 |
|
B |
21431 |
32644 |
|
B |
21432 |
32645 |
|
B |
21433 |
32646 |
|
B |
21435 |
32647 |
|
B |
21437 |
32648 |
|
B |
21412 |
32649 |
|
B |
21409 |
32650 |
|
B |
21404 |
32651 |
|
B |
21402 |
32652 |
|
B |
21388 |
32653 |
|
B |
21386 |