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 (32753,32754,32755,32756,32757,32758,32759,32760,32761,32762,32763,32764,32765,32766,32767,32768,32769,32770,32771,32772,32773,32774,32775,32776,32777,32778,32779,32780,32781,32782,32783,32784)) 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 |
32753 |
|
B |
21603 |
32754 |
|
B |
21601 |
32755 |
|
B |
21600 |
32756 |
|
B |
21599 |
32757 |
|
B |
21598 |
32758 |
|
B |
21596 |
32759 |
|
B |
21595 |
32760 |
|
B |
21593 |
32761 |
|
B |
21329 |
32762 |
|
B |
21334 |
32763 |
|
B |
21359 |
32764 |
|
B |
21357 |
32765 |
|
B |
21356 |
32766 |
|
B |
21354 |
32767 |
|
B |
21353 |
32768 |
|
B |
21333 |
32769 |
|
B |
21351 |
32770 |
|
B |
21350 |
32771 |
|
B |
21349 |
32772 |
|
B |
21348 |
32773 |
|
B |
21346 |
32774 |
|
B |
21345 |
32775 |
|
B |
21344 |
32776 |
|
B |
21343 |
32777 |
|
B |
21341 |
32778 |
|
B |
21340 |
32779 |
|
B |
21338 |
32780 |
|
B |
21337 |
32781 |
|
B |
21592 |
32782 |
|
B |
22094 |
32783 |
|
B |
22096 |
32784 |
|
B |
22097 |