Query time 0.00071
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 (30800,30801,30802,30803,30804,30805,30806,30807,30808,30809,30810,30811,30812,30813,30814,30815,30816,30817,30818,30819,30820,30821,30822,30823,30824,30825,30826,30827,30828,30829,30830,30831)) 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 |
30800 |
|
B |
23210 |
30801 |
|
B |
23208 |
30802 |
|
B |
23206 |
30803 |
|
B |
23205 |
30804 |
|
B |
23203 |
30805 |
|
B |
23201 |
30806 |
|
B |
23200 |
30807 |
|
B |
23199 |
30808 |
|
B |
23196 |
30809 |
|
B |
23194 |
30810 |
|
B |
23193 |
30811 |
|
B |
23190 |
30812 |
|
B |
23188 |
30813 |
|
B |
23186 |
30814 |
|
B |
23184 |
30815 |
|
B |
23183 |
30816 |
|
B |
23181 |
30817 |
|
B |
23179 |
30818 |
|
B |
23177 |
30819 |
|
B |
23175 |
30820 |
|
B |
23173 |
30821 |
|
B |
23171 |
30822 |
|
B |
23169 |
30823 |
|
B |
23167 |
30824 |
|
B |
23165 |
30825 |
|
B |
23163 |
30826 |
|
B |
23161 |
30827 |
|
B |
23155 |
30828 |
|
B |
23152 |
30829 |
|
B |
23151 |
30830 |
|
B |
23147 |
30831 |
|
B |
23146 |