Invisible and descending indexes

The invisible index is a special feature which will mark an index as unavailable for the optimizer. MySQL 8 will maintain invisible indexes and keep them up-to-date when data is modified. This will apply on indexes other than primary key. As we know, indexes are visible by default; we have to make them invisible explicitly at the time of creation, or by using the alter command. MySQL 8 provides the VISIBLE and INVISIBLE keywords to maintain index visibility. A descending index is the method of storing key values in descending order. A descending index is more efficient, as it can be scanned in the forward order. Let's see these indexes in detail, with examples.

Invisible index

As mention...