Query time 0.00057
JSON explain
{
"query_block": {
"select_id": 1,
"cost_info": {
"query_cost": "0.38"
},
"ordering_operation": {
"using_filesort": true,
"nested_loop": [
{
"table": {
"table_name": "attachments",
"access_type": "ref",
"possible_keys": [
"object_type",
"type"
],
"key": "object_type",
"used_key_parts": [
"object_type",
"object_id"
],
"key_length": "95",
"ref": [
"const",
"const"
],
"rows_examined_per_scan": 1,
"rows_produced_per_join": 0,
"filtered": "8.51",
"cost_info": {
"read_cost": "0.25",
"eval_cost": "0.01",
"prefix_cost": "0.35",
"data_read_per_join": "231"
},
"used_columns": [
"attachment_id",
"object_type",
"object_id",
"type",
"position",
"filename",
"filesize",
"usergroup_ids",
"status",
"file_type",
"url",
"on_server"
],
"attached_condition": "((`goimagine`.`attachments`.`type` = 'M') and ((`goimagine`.`attachments`.`usergroup_ids` = '') or (0 <> find_in_set(0,`goimagine`.`attachments`.`usergroup_ids`)) or (0 <> find_in_set(1,`goimagine`.`attachments`.`usergroup_ids`))) and (`goimagine`.`attachments`.`status` = 'A'))"
}
},
{
"table": {
"table_name": "attachment_descriptions",
"access_type": "eq_ref",
"possible_keys": [
"PRIMARY"
],
"key": "PRIMARY",
"used_key_parts": [
"attachment_id",
"lang_code"
],
"key_length": "9",
"ref": [
"goimagine.attachments.attachment_id",
"const"
],
"rows_examined_per_scan": 1,
"rows_produced_per_join": 0,
"filtered": "100.00",
"cost_info": {
"read_cost": "0.02",
"eval_cost": "0.01",
"prefix_cost": "0.38",
"data_read_per_join": "66"
},
"used_columns": [
"attachment_id",
"lang_code",
"description"
]
}
}
]
}
}
}