Deferred and Immediate Execution

The timing of LINQ query execution depends on how the query is evaluated. There are essentially two ways of executing a LINQ query:

• Deferred execution: The LINQ query only executes when we try to address an item from a resulting collection.

• Immediate execution: The LINQ query executes immediately after construction.

Let us explore these concepts in detail.

Deferred execution

There are three steps to creating and running a LINQ query:

1. Creating or attaining a data source

2. Creating a query

3. Executing the query

Deferred execution means that our query is not executed the moment it is created. We define a data source and query using top-level statements.