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 (9869,9870,9871,9872,9873,9874,9875,9876,9877,9878,9879,9880,9881,9882,9883,9884,9885,9886,9887,9888,9889,9890,9891,9892,9893,9894,9895,9896,9897,9898,9899,9900)) 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 |
9869 |
|
D |
4918 |
9870 |
|
D |
4919 |
9871 |
|
D |
4920 |
9872 |
|
D |
4921 |
9873 |
|
D |
4922 |
9874 |
|
D |
4923 |
9875 |
|
D |
4924 |
9876 |
|
D |
4925 |
9877 |
|
D |
4906 |
9878 |
|
D |
4907 |
9879 |
|
D |
4908 |
9880 |
|
D |
4909 |
9881 |
|
D |
4910 |
9882 |
|
D |
4911 |
9883 |
|
D |
4912 |
9884 |
|
D |
4913 |
9885 |
|
D |
4914 |
9886 |
|
D |
4915 |
9887 |
|
D |
4897 |
9888 |
|
D |
4898 |
9889 |
|
D |
4899 |
9890 |
|
D |
4900 |
9891 |
|
D |
4901 |
9892 |
|
D |
4902 |
9893 |
|
D |
4903 |
9894 |
|
D |
4904 |
9895 |
|
D |
4905 |
9896 |
|
D |
4887 |
9897 |
|
D |
4888 |
9898 |
|
D |
4889 |
9899 |
|
D |
4890 |
9900 |
|
D |
4891 |