Query time 0.00075
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 (29282,29283,29314,29341,29690,29694,29702,29799,30319,30339,30770,30781,30782,30783,30787,30794,30799,30815,30860,30873,30876,30899,30911,30920,30931,30937,30939,30943,30957,30972)) 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 |
29282 |
|
B |
20337 |
29283 |
|
B |
20205 |
29314 |
|
B |
20331 |
29341 |
|
B |
20291 |
29690 |
|
B |
20458 |
29694 |
|
B |
20451 |
29702 |
|
B |
20437 |
29799 |
|
B |
20669 |
30319 |
|
B |
22435 |
30770 |
|
B |
22500 |
30781 |
|
B |
22483 |
30782 |
|
B |
22482 |
30783 |
|
B |
22480 |
30787 |
|
B |
23071 |
30794 |
|
B |
23058 |
30799 |
|
B |
23212 |
30815 |
|
B |
23183 |
30860 |
|
B |
22617 |
30873 |
|
B |
22601 |
30876 |
|
B |
22596 |
30899 |
|
B |
23288 |
30911 |
|
B |
22722 |
30920 |
|
B |
22702 |
30931 |
|
B |
23273 |
30937 |
|
B |
23014 |
30939 |
|
B |
23263 |
30943 |
|
B |
23019 |
30957 |
|
B |
23246 |
30972 |
|
B |
23381 |