Can LINQ Perform Direct SQL Updates Without Selecting Data First?

Direct Updates with LINQ without Select

When dealing directly with SQL, you can generate update commands with conditionals without running a select statement. In LINQ, the common pattern involves selecting entities, modifying them, and submitting the changes. However, is it possible to perform a direct update using LINQ and deferred execution without transmitting data to the client?

The provided LINQ query attempts to perform a direct update, but it includes a select clause. While LINQ has all the information needed to generate an update command, there is no "set" keyword equivalent in LINQ.

Solution:

To create direct update statements using LINQ-to-SQL:

1. Create an object and set its key properties:

Foo foo = new Foo { FooId = fooId };

2. Attach the object to the context:

context.Foos.Attach(foo);

3. Set the properties you want to update:

foo.Name = "test";

4. Submit the changes:

context.SubmitChanges();

Note:

• Ensure that the UpdateCheck property for all properties in your Dbml is set to "Never."
• To set a property to null, initialize the object with a non-null value (e.g., Name="###").
• To check for a timestamp while updating, set the UpdateCheck property of the Modified property in your Dbml to "Always."

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