Query time 0.00066
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 (16317,16318,16319,16320,16321,16322,16323,16324,16325,16326,16327,16328,16329,16331,16332,16333,16334,16335,16336,16337,16338,16339,16340,16341,16342,16343,16344,16345,16346,16347)) 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 |
16317 |
|
B |
8553 |
16318 |
|
B |
8554 |
16319 |
|
B |
8555 |
16320 |
|
B |
8556 |
16321 |
|
B |
8558 |
16322 |
|
B |
8560 |
16323 |
|
B |
8507 |
16324 |
|
B |
8510 |
16325 |
|
B |
8511 |
16326 |
|
B |
8513 |
16327 |
|
B |
8515 |
16328 |
|
B |
8517 |
16329 |
|
B |
8518 |
16331 |
|
B |
8524 |
16332 |
|
B |
8526 |
16333 |
|
B |
8528 |
16334 |
|
B |
8529 |
16335 |
|
B |
8531 |
16336 |
|
B |
8534 |
16337 |
|
B |
8536 |
16338 |
|
B |
8538 |
16339 |
|
B |
8541 |
16340 |
|
B |
8543 |
16341 |
|
B |
8544 |
16342 |
|
B |
8546 |
16343 |
|
B |
8547 |
16344 |
|
B |
8423 |
16345 |
|
B |
8421 |
16346 |
|
B |
8420 |
16347 |
|
B |
7955 |