Query time 0.00077
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 (6957,6958,6959,6960,6961,6962,6963,6964,6965,6966,6967,6968,6969,6970,6971,6972,6974,6977,6978,6979,4497,4498,4499,4500,4501,4502,4503,4504,4505,4506,4507,4509)) 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 |
4497 |
|
D |
2623 |
4498 |
|
D |
4324 |
4499 |
|
D |
4337 |
4500 |
|
D |
2638 |
4501 |
|
D |
2636 |
4502 |
|
D |
2624 |
4503 |
|
D |
2625 |
4504 |
|
D |
4296 |
4505 |
|
D |
4298 |
4506 |
|
D |
4299 |
4507 |
|
D |
4300 |
4509 |
|
D |
4307 |
6957 |
|
D |
2968 |
6958 |
|
D |
2969 |
6959 |
|
D |
2948 |
6960 |
|
D |
2970 |
6961 |
|
D |
2971 |
6962 |
|
D |
2972 |
6963 |
|
D |
2973 |
6964 |
|
D |
2974 |
6965 |
|
D |
2950 |
6966 |
|
D |
2975 |
6967 |
|
D |
2951 |
6968 |
|
D |
2952 |
6969 |
|
D |
2953 |
6970 |
|
D |
2954 |
6971 |
|
D |
2955 |
6972 |
|
D |
2976 |
6974 |
|
D |
2960 |
6977 |
|
D |
2977 |
6978 |
|
D |
2979 |
6979 |
|
D |
2980 |