我有以下Mysql查询explainSELECTcount(*)asassetCountFROMMdhRawAssetmwheresysCreationDate>date_add(now(),INTERVAL-1DAY)ANDsysCreationDate结果:|id|select_type|table|type|possible_keys|1|SIMPLE|m|range|MdhRawAsset_on_sysCreationDate,MdhRawAsset_itemType--------------------------------------------------------