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 (32484,32485,32486,32487,32488,32489,32490,32491,32492,32493,32494,32495,32496,32497,32499,32500,32501,32502,32503,32504,32505,32506,32507,32508,32509,32510,32511,32512,32513,32514,32515,32516)) 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 |
32484 |
|
B |
20886 |
32485 |
|
B |
20887 |
32486 |
|
B |
20888 |
32487 |
|
B |
20889 |
32488 |
|
B |
20890 |
32489 |
|
B |
20891 |
32490 |
|
B |
20892 |
32491 |
|
B |
20893 |
32492 |
|
B |
20894 |
32493 |
|
B |
20895 |
32494 |
|
B |
20896 |
32495 |
|
B |
20898 |
32496 |
|
B |
20899 |
32497 |
|
B |
20900 |
32499 |
|
B |
20901 |
32500 |
|
B |
20902 |
32501 |
|
B |
20903 |
32502 |
|
B |
20905 |
32503 |
|
B |
20906 |
32504 |
|
B |
20907 |
32505 |
|
B |
20908 |
32506 |
|
B |
20909 |
32507 |
|
B |
20910 |
32508 |
|
B |
20911 |
32509 |
|
B |
20912 |
32510 |
|
B |
20913 |
32511 |
|
B |
22138 |
32512 |
|
B |
22140 |
32513 |
|
B |
22158 |
32514 |
|
B |
22153 |
32515 |
|
B |
22155 |
32516 |
|
B |
22151 |