Query time 0.00132
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 (3715,3716,3717,3718,3719,3720,3721,3722,3723,3724,3725,3726,3727,3728,3729,3730,3731,3732,3733,3734,3735,3737,3738,3740,3741,3742,3743,3747,3748,3749)) 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 |
3715 |
|
D |
2070 |
3716 |
|
D |
2071 |
3717 |
|
D |
2072 |
3718 |
|
D |
2073 |
3719 |
|
D |
2074 |
3720 |
|
D |
2075 |
3721 |
|
D |
2076 |
3722 |
|
D |
2077 |
3723 |
|
D |
2078 |
3724 |
|
D |
2079 |
3725 |
|
D |
2080 |
3726 |
|
D |
2081 |
3727 |
|
D |
2082 |
3728 |
|
D |
2083 |
3729 |
|
D |
2084 |
3730 |
|
D |
2085 |
3731 |
|
D |
2086 |
3732 |
|
D |
2087 |
3733 |
|
D |
2088 |
3734 |
|
D |
2089 |
3735 |
|
D |
2090 |
3737 |
|
D |
2092 |
3738 |
|
D |
2093 |
3740 |
|
D |
2095 |
3742 |
|
D |
2096 |
3743 |
|
D |
2097 |
3747 |
|
D |
2100 |
3748 |
|
D |
2101 |
3749 |
|
D |
2102 |