Advanced SQL Concepts For Software Engineers

Here are concise and clear answers to the advanced SQL interview questions listed previously:

Clustered vs. Non-Clustered Indexes

Clustered Index: Determines the physical order of data in the table. Each table can have only one clustered index. Use it for columns frequently used in ORDER BY or JOIN clauses.
Non-Clustered Index: Stores a separate structure with pointers to the data rows. Multiple non-clustered indexes can exist on a table. Use it when you need to speed up searches on columns that are not the primary key.

Optimizing a Slow-Running Query

Steps:

Analyze the query execution pl...