Query time 0.00058
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 (3570,3571,3572,3579,3586,3590,3591,3592,3593,3594,3595,3596,3597,3598,3599,3602,3603,3604,3605,3606,3607,3608,3610,3611,3612,3613,3614,3615,3616,3617)) 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 |
3570 |
|
D |
2022 |
3571 |
|
D |
2023 |
3572 |
|
D |
2024 |
3579 |
|
D |
2028 |
3586 |
|
D |
2041 |
3590 |
|
D |
1897 |
3591 |
|
D |
1898 |
3592 |
|
D |
1900 |
3593 |
|
D |
1902 |
3594 |
|
D |
1903 |
3595 |
|
D |
1904 |
3596 |
|
D |
1905 |
3597 |
|
D |
1906 |
3598 |
|
D |
1907 |
3599 |
|
D |
1908 |
3602 |
|
D |
1910 |
3603 |
|
D |
1911 |
3604 |
|
D |
1912 |
3605 |
|
D |
1913 |
3606 |
|
D |
1914 |
3607 |
|
D |
1616 |
3608 |
|
D |
1916 |
3610 |
|
D |
1918 |
3611 |
|
D |
1919 |
3612 |
|
D |
1920 |
3613 |
|
D |
1929 |
3614 |
|
D |
1930 |
3615 |
|
D |
1923 |
3616 |
|
D |
1924 |
3617 |
|
D |
1925 |