一般来说，索引扫描是访问数据的最有效的方法，尤其是表很大但符合条件的行很少的时候。

Index scans are usually the most efficient way to access data, especially when the table is large but the number of qualified rows is small.

youdao

而且，虽然在type - 2索引扫描中，被删除的行不会被跳过，但是除非同时设置了注册表变量db2_skipdeleted，否则在表扫描访问中，被删除的行将被无条件跳过。

Furthermore, deleted rows are skipped unconditionally on table scan access while deleted keys are not skipped for type-2 index scans unless the registry variable DB2_SKIPDELETED is also set.

youdao