Query time 0.00064
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 (2734,2735,2694,2695,2696,2697,2698,2699,2700,2701,2675,2676,2677,2678,2679,2680,2681,2682,2683,2684,2685,2686,2687,2688,2689,2607,2608,2609,2610,2611)) 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 |
2608 |
|
D |
1137 |
2609 |
|
D |
1138 |
2610 |
|
D |
1139 |
2611 |
|
D |
1140 |
2675 |
|
D |
1144 |
2676 |
|
D |
1145 |
2677 |
|
D |
1146 |
2678 |
|
D |
1147 |
2679 |
|
D |
1148 |
2680 |
|
D |
1165 |
2681 |
|
D |
1149 |
2682 |
|
D |
1150 |
2683 |
|
D |
1151 |
2684 |
|
D |
1152 |
2685 |
|
D |
1153 |
2686 |
|
D |
1154 |
2687 |
|
D |
1155 |
2688 |
|
D |
1156 |
2689 |
|
D |
1157 |
2734 |
|
D |
1124 |
2735 |
|
D |
1132 |