Certainly! Here's an SEO-friendly HTML answer for the interview question about the difference between a clustered index and a non-clustered index in a database:

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Clustered Index vs. Non-Clustered Index in a Database

In a database, a clustered index determines the physical order of data rows in a table based on the indexed column. This means the actual data rows are stored in the order of the clustered index key, allowing for fast retrieval but limiting only one clustered index per table.

On the other hand, a non-clustered index does not affect the physical order of the rows in the table. Instead, a separate structure is created that contains the indexed column's values along with pointers to the actual data rows. Multiple non-clustered indexes can be created on a single table, providing flexibility but potentially slower retrieval compared to clustered indexes.

In summary, while clustered indexes dictate the physical order of data, non-clustered indexes provide additional access paths to the data. Choosing between them depends on the specific data access patterns and performance requirements of the database system.

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