Query time 0.00074
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 (30896,30897,30898,30899,30900,30901,30902,30903,30904,30905,30906,30907,30908,30909,30910,30911,30912,30913,30914,30915,30916,30917,30918,30919,30920,30921,30922,30923,30924,30925,30926,30927)) 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 |
30896 |
|
B |
23296 |
30897 |
|
B |
23292 |
30898 |
|
B |
23289 |
30899 |
|
B |
23288 |
30900 |
|
B |
23287 |
30901 |
|
B |
23285 |
30902 |
|
B |
23284 |
30903 |
|
B |
23282 |
30904 |
|
B |
23281 |
30905 |
|
B |
23279 |
30906 |
|
B |
23277 |
30907 |
|
B |
23275 |
30908 |
|
B |
22728 |
30909 |
|
B |
22727 |
30910 |
|
B |
22724 |
30911 |
|
B |
22722 |
30912 |
|
B |
22721 |
30913 |
|
B |
22719 |
30914 |
|
B |
22716 |
30915 |
|
B |
22715 |
30916 |
|
B |
22714 |
30917 |
|
B |
22712 |
30918 |
|
B |
22705 |
30919 |
|
B |
22703 |
30920 |
|
B |
22702 |
30921 |
|
B |
22699 |
30922 |
|
B |
22698 |
30923 |
|
B |
22695 |
30924 |
|
B |
22693 |
30925 |
|
B |
22691 |
30926 |
|
B |
22685 |
30927 |
|
B |
22684 |