Description: A secondary index is an index that is not the primary key, allowing for more efficient data querying. In NoSQL databases, secondary indexes are essential for improving the performance of queries that do not rely on the primary key. Unlike primary indexes, which are designed for fast and efficient data access through a unique key, secondary indexes allow for searches on columns that are not part of the primary key. This is particularly useful in scenarios where data needs to be accessed through multiple attributes or where queries are more complex. Secondary indexes are implemented in a way that maintains the scalability and availability of the system, allowing developers to optimize their applications without compromising performance. However, it is important to note that excessive use of secondary indexes can lead to increased write costs and greater complexity in data management. Therefore, their implementation should be carefully considered and designed to meet the specific needs of the application.
