How are LINQ expressions used in EF Core?
For example, the code shown so far uses the built-in LINQ to Objects provider. Your EF Core projects use the EF Core provider that maps to your database. The query is defined and converted to an expression tree. I’ll cover expressions more in a moment. The query is executed and the data is returned.
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How is LINQ syntax consistent across data sources?
LINQ provides a standard language and syntax that is consistent across all data sources. Consider this LINQ query (you can paste it into a console application and run it yourself): Because someNumbers is an IEnumerable, LINQ to Objects parses the query.
What are the phases of a LINQ query?
Every LINQ query has three phases: A data source, known as a provider, is configured against which the query will act. For example, the code shown so far uses the built-in LINQ to Objects provider. Your EF Core projects use the EF Core provider that maps to your database. The query is defined and converted to an expression tree.
How is LINQ used to generate T-SQL?
Since someNumbers is an IEnumerable , LINQ to Objects parses the query. The same query syntax can be used with a tool like Entity Framework Core to generate T-SQL that runs against a relational database.
When to use Func in LINQ for entities?
When you use Func, your lambda is compiled to IL, but when you use Expression, it’s an expression tree that Linq to Entities can traverse and convert. This works with expressions that Linq to Entities understands.
What does the call to invoke do in LINQ?
The important point here is that we did not lose the expression tree of this inner expression. The inner expression is followed by the Invoke method call and is part of the Add expression that represents the sum in the test. The second line represents the expression tree created by the Expand method.
How to invoke extension method in LINQ query?
To use the expression, you must use the Invoke extension method that is declared in the ExpressionExtensions class (EeekSoft.Expressions namespace).