What is a query plan?.

The query plan is an internal representation of how the database management system (DBMS) or ORM will execute a data query.

It describes a sequence of operations such as table scans, filtering, sorting, joins, which are necessary to obtain the result.

In C#, when working with LINQ, the query plan is formed during the compilation of the expression and can be optimized by the data provider (for example, Entity Framework), which translates the LINQ query into SQL with an optimal execution plan.

Understanding the query plan helps optimize performance, identify bottlenecks, and improve query structure.