Query time 0.00104
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 (9549,9550,9551,9552,9553,9554,9555,9556,9557,9558,9559,9560,9561,9562,9563,9564,9565,9566,9567,9568,9569,9570,9571,9572,9573,9574,9575,9576,9577,9578,9579,9580)) 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 |
9549 |
|
B |
6363 |
9550 |
|
B |
6364 |
9551 |
|
B |
6365 |
9552 |
|
B |
6366 |
9553 |
|
B |
6367 |
9554 |
|
B |
6369 |
9555 |
|
B |
6370 |
9556 |
|
B |
6371 |
9557 |
|
B |
6372 |
9558 |
|
B |
6373 |
9559 |
|
B |
6374 |
9560 |
|
B |
6415 |
9561 |
|
B |
6416 |
9562 |
|
B |
6417 |
9563 |
|
B |
6418 |
9564 |
|
B |
6419 |
9565 |
|
B |
6420 |
9566 |
|
B |
6421 |
9567 |
|
B |
6422 |
9568 |
|
B |
6425 |
9569 |
|
B |
6426 |
9570 |
|
B |
6424 |
9571 |
|
B |
6423 |
9572 |
|
B |
6438 |
9573 |
|
B |
6439 |
9574 |
|
B |
6427 |
9575 |
|
B |
6428 |
9576 |
|
B |
6429 |
9577 |
|
B |
6430 |
9578 |
|
B |
6431 |
9579 |
|
B |
6432 |
9580 |
|
B |
6433 |