What are the disadvantages of using indexes in SQL?

What are the disadvantages of using indexes in SQL?

While indexes can improve query performance, they also have some disadvantages. For instance, they can slow down data modification operations like INSERT, UPDATE, and DELETE because the index needs to be updated as well.

Can you explain how indexes affect performance during data modifications?

Sure! When you modify data, the database must not only change the data itself but also update the associated indexes. This can lead to increased overhead and slower performance, especially if there are many indexes on a table.

Are there any specific scenarios where indexes should be avoided?

Yes, indexes should be avoided in scenarios where the table has a high rate of data changes or when the indexed columns have low selectivity, meaning they don't significantly narrow down the result set.

What about the storage costs of indexes?

Indexes consume additional disk space, which can be significant for large tables. This can lead to increased storage costs and may require more maintenance.