Query time 0.00068
JSON explain
{
"query_block": {
"select_id": 1,
"cost_info": {
"query_cost": "216.01"
},
"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": 30,
"rows_produced_per_join": 30,
"filtered": "100.00",
"index_condition": "((`portal`.`q_discussion`.`object_id` in (14849,14850,14851,14852,14853,14855,14858,14860,14861,14862,14875,14880,14881,14894,14933,15229,15284,15285,15288,15519,15712,15713,15726,15772,15778,15837,15866,15867,15868,15872)) and (`portal`.`q_discussion`.`object_type` = 'P'))",
"cost_info": {
"read_cost": "66.01",
"eval_cost": "6.00",
"prefix_cost": "72.01",
"data_read_per_join": "480"
},
"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": 60,
"filtered": "100.00",
"cost_info": {
"read_cost": "60.00",
"eval_cost": "12.00",
"prefix_cost": "144.01",
"data_read_per_join": "26K"
},
"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": 60,
"filtered": "100.00",
"cost_info": {
"read_cost": "60.00",
"eval_cost": "12.00",
"prefix_cost": "216.01",
"data_read_per_join": "960"
},
"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 |
14849 |
|
B |
11442 |
14850 |
|
B |
11346 |
14851 |
|
B |
11344 |
14852 |
|
B |
11339 |
14853 |
|
B |
11443 |
14855 |
|
B |
11366 |
14858 |
|
B |
11371 |
14860 |
|
B |
11376 |
14861 |
|
B |
11377 |
14862 |
|
B |
11380 |
14875 |
|
B |
11400 |
14880 |
|
B |
11445 |
14881 |
|
B |
11446 |
14894 |
|
B |
11261 |
14933 |
|
B |
11334 |
15229 |
|
B |
10688 |
15284 |
|
B |
10479 |
15285 |
|
B |
10480 |
15288 |
|
B |
10483 |
15519 |
|
B |
10080 |
15712 |
|
B |
9733 |
15713 |
|
B |
9734 |
15726 |
|
B |
9751 |
15772 |
|
B |
9594 |
15778 |
|
B |
9605 |
15837 |
|
B |
9455 |
15866 |
|
B |
9483 |
15867 |
|
B |
9488 |
15868 |
|
B |
9487 |
15872 |
|
B |
9502 |