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aspnetcore/tutorials/first-mvc-app/search.md
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@ -33,7 +33,7 @@ If the `searchString` parameter contains a string, the movies query is modified
[!code-csharp[](~/tutorials/first-mvc-app/start-mvc/sample/MvcMovie60/Controllers/MoviesController.cs?name=IndexSearchCheckForNull)]
The `s => s.Title.Contains(searchString)` code above is a [Lambda Expression](/dotnet/csharp/programming-guide/statements-expressions-operators/lambda-expressions). Lambdas are used in method-based [LINQ](/dotnet/standard/using-linq) queries as arguments to standard query operator methods such as the <xref:System.Linq.Enumerable.Where%2A> method or `Contains` (used in the code above). LINQ queries are not executed when they're defined or when they're modified by calling a method such as `Where`, `Contains`, or `OrderBy`. Rather, query execution is deferred. That means that the evaluation of an expression is delayed until its realized value is actually iterated over or the `ToListAsync` method is called. For more information about deferred query execution, see [Query Execution](/dotnet/framework/data/adonet/ef/language-reference/query-execution).
The `s => s.Title!.Contains(searchString)` code above is a [Lambda Expression](/dotnet/csharp/programming-guide/statements-expressions-operators/lambda-expressions). Lambdas are used in method-based [LINQ](/dotnet/standard/using-linq) queries as arguments to standard query operator methods such as the <xref:System.Linq.Enumerable.Where%2A> method or `Contains` (used in the code above). LINQ queries are not executed when they're defined or when they're modified by calling a method such as `Where`, `Contains`, or `OrderBy`. Rather, query execution is deferred. That means that the evaluation of an expression is delayed until its realized value is actually iterated over or the `ToListAsync` method is called. For more information about deferred query execution, see [Query Execution](/dotnet/framework/data/adonet/ef/language-reference/query-execution).
Note: The <xref:System.Data.Objects.DataClasses.EntityCollection%601.Contains%2A> method is run on the database, not in the c# code shown above. The case sensitivity on the query depends on the database and the collation. On SQL Server, `Contains` maps to [SQL LIKE](/sql/t-sql/language-elements/like-transact-sql), which is case insensitive. In SQLite, with the default collation, it's case sensitive.