Invisible Indexes

When you create any index, by default, the optimizer is aware of the index and it starts taking account of the index in all its cost estimations. However, there are occasions when you may want to create an index but control when the optimizer can use the index. You can hide an index from the optimizer by creating an index as an “invisible” index. You can also alter the status of an existing index by making it invisible. You can toggle the status of the index between visible and invisible as you please.

images Note Since the database must continue to maintain a visible index when inserts, deletes, and updates occur, it is important ...

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