Query time 0.00070
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 (9581,9582,9583,9584,9585,9586,9587,9588,9589,9590,9591,9592,9593,9594,9595,9596,9597,9598,9599,9600,9601,9602,9603,9604,9605,9606,9607,9608,9609,9610,9611,9612)) 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 |
9581 |
|
B |
6434 |
9582 |
|
B |
6466 |
9583 |
|
B |
6440 |
9584 |
|
B |
6442 |
9585 |
|
B |
6443 |
9586 |
|
B |
6441 |
9587 |
|
B |
6467 |
9588 |
|
B |
6468 |
9589 |
|
B |
6469 |
9590 |
|
B |
6458 |
9591 |
|
B |
6457 |
9592 |
|
B |
6473 |
9593 |
|
B |
6474 |
9594 |
|
B |
6475 |
9595 |
|
B |
6476 |
9596 |
|
B |
6477 |
9597 |
|
B |
6478 |
9598 |
|
B |
6479 |
9599 |
|
B |
6480 |
9600 |
|
B |
6481 |
9601 |
|
B |
6482 |
9602 |
|
B |
6483 |
9603 |
|
B |
6485 |
9604 |
|
B |
6486 |
9605 |
|
B |
6487 |
9606 |
|
B |
6488 |
9607 |
|
B |
6489 |
9608 |
|
B |
6490 |
9609 |
|
B |
6491 |
9610 |
|
B |
6492 |
9611 |
|
B |
6495 |
9612 |
|
B |
6504 |