Query time 0.00045
JSON explain
{
"query_block": {
"select_id": 1,
"cost_info": {
"query_cost": "1.70"
},
"grouping_operation": {
"using_temporary_table": true,
"using_filesort": false,
"nested_loop": [
{
"table": {
"table_name": "dp",
"access_type": "ALL",
"possible_keys": [
"thread_id",
"thread_id_2"
],
"rows_examined_per_scan": 8,
"rows_produced_per_join": 1,
"filtered": "12.50",
"cost_info": {
"read_cost": "1.22",
"eval_cost": "0.10",
"prefix_cost": "1.32",
"data_read_per_join": "448"
},
"used_columns": [
"post_id",
"thread_id",
"status"
],
"attached_condition": "(`s2cart`.`dp`.`status` = 'A')"
}
},
{
"table": {
"table_name": "cscart_discussion",
"access_type": "eq_ref",
"possible_keys": [
"PRIMARY",
"object_id"
],
"key": "PRIMARY",
"used_key_parts": [
"thread_id"
],
"key_length": "3",
"ref": [
"s2cart.dp.thread_id"
],
"rows_examined_per_scan": 1,
"rows_produced_per_join": 0,
"filtered": "5.00",
"cost_info": {
"read_cost": "0.25",
"eval_cost": "0.01",
"prefix_cost": "1.67",
"data_read_per_join": "1"
},
"used_columns": [
"thread_id",
"object_id",
"object_type"
],
"attached_condition": "((`s2cart`.`cscart_discussion`.`object_id` in (243684,51603,119291,275040,277987,277101,275765,277911)) and (`s2cart`.`cscart_discussion`.`object_type` = 'P'))"
}
},
{
"table": {
"table_name": "p",
"access_type": "eq_ref",
"possible_keys": [
"PRIMARY"
],
"key": "PRIMARY",
"used_key_parts": [
"product_id"
],
"key_length": "3",
"ref": [
"s2cart.cscart_discussion.object_id"
],
"rows_examined_per_scan": 1,
"rows_produced_per_join": 0,
"filtered": "100.00",
"using_index": true,
"cost_info": {
"read_cost": "0.02",
"eval_cost": "0.01",
"prefix_cost": "1.70",
"data_read_per_join": "393"
},
"used_columns": [
"product_id"
]
}
}
]
}
}
}