Query time 0.00076
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 (30766,30767,30769,30770,30771,30772,30773,30774,30775,30776,30777,30778,30779,30781,30782,30783,30784,30785,30786,30787,30788,30789,30790,30791,30792,30793,30794,30795,30796,30797,30798,30799)) 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 |
30766 |
|
B |
22505 |
30767 |
|
B |
22503 |
30769 |
|
B |
22501 |
30770 |
|
B |
22500 |
30771 |
|
B |
22499 |
30772 |
|
B |
22497 |
30773 |
|
B |
22496 |
30774 |
|
B |
22494 |
30775 |
|
B |
22492 |
30776 |
|
B |
22490 |
30777 |
|
B |
22486 |
30779 |
|
B |
22485 |
30781 |
|
B |
22483 |
30782 |
|
B |
22482 |
30783 |
|
B |
22480 |
30784 |
|
B |
23080 |
30785 |
|
B |
23079 |
30786 |
|
B |
23075 |
30787 |
|
B |
23071 |
30788 |
|
B |
23069 |
30789 |
|
B |
23068 |
30790 |
|
B |
23067 |
30791 |
|
B |
23066 |
30792 |
|
B |
23064 |
30793 |
|
B |
23060 |
30794 |
|
B |
23058 |
30795 |
|
B |
23217 |
30796 |
|
B |
23215 |
30797 |
|
B |
23214 |
30798 |
|
B |
23213 |
30799 |
|
B |
23212 |