.NET Tips and Tricks

Blog archive

Save Some Time Deleting Entities in Entity Framework: RemoveRange

When it comes to speeding up your application, your best opportunity is to reduce trips to your database. So, when you see a method like RemoveRange on a DbContext collection, you might think that's an opportunity to delete a bunch of objects in less time than deleting those same objects one by one. You'd be right…but not because you're saving trips to your database.

Here's some sample code that will delete all of the SalesOrderHeaders with a DueDate before the current date:

Dim res = From so In db.SalesOrderHeaders 
          Where so.DueDate < DateTime.Now 
          Select so 
db.SalesOrderHeaders.RemoveRange(res)  
db.SaveChanges

This will run faster than, for example, looping through the res collection and passing each object to the SalesOrderHeaders Remove method before calling SaveChanges. However, either way, you'll still be making one trip to the database, submitting one SQL delete statement for every SalesOrderHeader that's being deleted.

Where you'll save time is in the overhead around removing the objects from the SalesOrderHeaders collection (especially around change tracking which will run once with RemoveRange rather than once for each object with Remove).

Posted by Peter Vogel on 06/21/2016


comments powered by Disqus

Featured

  • IDE Irony: Coding Errors Cause 'Critical' Vulnerability in Visual Studio

    In a larger-than-normal Patch Tuesday, Microsoft warned of a "critical" vulnerability in Visual Studio that should be fixed immediately if automatic patching isn't enabled, ironically caused by coding errors.

  • Building Blazor Applications

    A trio of Blazor experts will conduct a full-day workshop for devs to learn everything about the tech a a March developer conference in Las Vegas keynoted by Microsoft execs and featuring many Microsoft devs.

  • Gradient Boosting Regression Using C#

    Dr. James McCaffrey from Microsoft Research presents a complete end-to-end demonstration of the gradient boosting regression technique, where the goal is to predict a single numeric value. Compared to existing library implementations of gradient boosting regression, a from-scratch implementation allows much easier customization and integration with other .NET systems.

  • Microsoft Execs to Tackle AI and Cloud in Dev Conference Keynotes

    AI unsurprisingly is all over keynotes that Microsoft execs will helm to kick off the Visual Studio Live! developer conference in Las Vegas, March 10-14, which the company described as "a must-attend event."

  • Copilot Agentic AI Dev Environment Opens Up to All

    Microsoft removed waitlist restrictions for some of its most advanced GenAI tech, Copilot Workspace, recently made available as a technical preview.

Subscribe on YouTube