Difference between Clustered Index and Non-Clustered Index in DB2

A clustered index in DB2 physically arranges the data on disk based on the indexed column's values. This means the rows are stored in the same order as the clustered index, providing faster retrieval for range queries and sequential access.

On the other hand, a non-clustered index in DB2 creates a separate data structure that points to the physical location of the rows. This allows for quicker lookups based on the indexed column but may require additional disk reads to retrieve the actual data.

When considering performance, clustered indexes are typically faster for range queries and table scans, while non-clustered indexes excel at single-row lookups and support for multiple indexes on a table.

Ultimately, the choice between a clustered and non-clustered index in DB2 depends on the specific use case, access patterns, and overall performance requirements of the application.