Leveraging EF Core 7.0 Features for Efficient Database Operations (2023)

In the ever-evolving landscape of Entity Framework (EF) Core, version 7.0 introduces powerful methods to handle database operations with unparalleled efficiency. Among these, ExecuteUpdate and ExecuteDelete stand out as game-changers, offering a streamlined approach to save data without the traditional burden of change tracking and SaveChanges() method.

ExecuteDelete: Streamlining Database Cleanup

When faced with the task of deleting entities based on specific criteria, ExecuteDelete emerges as a concise and efficient alternative. Let's consider a scenario where all blogs with a rating below a certain threshold need deletion:

context.Blogs.Where(b => b.Rating < 3).ExecuteDelete();

This elegant one-liner leverages LINQ operators to identify the target entities and instructs EF to execute a SQL DELETE statement, bypassing the need to load and track individual entities. The resulting SQL is succinct and performs efficiently in the database:

DELETE FROM [Blogs] WHERE [Rating] < 3

ExecuteUpdate: Effortless Entity Modification

ExecuteUpdate extends the simplicity of ExecuteDelete to entity modification scenarios. Suppose we want to update blogs with a rating below 3, setting the 'IsVisible' property to false:

context.Blogs
    .Where(b => b.Rating < 3)
    .ExecuteUpdate(setters => setters.SetProperty(b => b.IsVisible, false));

This concise code achieves the desired modification, resulting in the following SQL:

UPDATE [Blogs] SET [IsVisible] = CAST(0 AS bit) WHERE [Rating] < 3

Updating Multiple Properties in a Single Stroke

ExecuteUpdate excels in efficiency by allowing the simultaneous update of multiple properties. To set 'IsVisible' to false and 'Rating' to zero, chaining SetProperty calls together is all it takes:

context.Blogs
    .Where(b => b.Rating < 3)
    .ExecuteUpdate(setters => setters
        .SetProperty(b => b.IsVisible, false)
        .SetProperty(b => b.Rating, 0));

The resulting SQL elegantly captures this dual modification:

UPDATE [Blogs] SET [Rating] = 0, [IsVisible] = CAST(0 AS bit) WHERE [Rating] < 3

Dynamic Updates with ExecuteUpdate

ExecuteUpdate's flexibility shines when referencing existing property values. To increment the rating of all matching blogs by one, the lambda function allows seamless reference to the current rating:

context.Blogs
    .Where(b => b.Rating < 3)
    .ExecuteUpdate(setters => setters.SetProperty(b => b.Rating, b => b.Rating + 1));

The resulting SQL succinctly captures this dynamic update:

UPDATE [Blogs] SET [Rating] = [Rating] + 1 WHERE [Rating] < 3

Handling Transactions for Consistency

ExecuteUpdate and ExecuteDelete operate independently and do not implicitly start transactions. To ensure consistency across multiple operations, explicit transaction management is advisable:

using (var transaction = context.Database.BeginTransaction()){
    context.Blogs.ExecuteUpdate(/* some update */);
    context.Blogs.ExecuteUpdate(/* another update */);
    // Additional operations
    transaction.Commit();
}

Explicitly starting a transaction guarantees that either all operations succeed or none are applied, maintaining database integrity.

Concurrency Control and Rows Affected

While ExecuteUpdate and ExecuteDelete lack automatic concurrency control, they provide the number of affected rows. This information proves invaluable for implementing custom concurrency checks:

var numUpdated = context.Blogs
    .Where(b => b.Id == id && b.ConcurrencyToken == concurrencyToken)
    .ExecuteUpdate(/* ... */);

if (numUpdated == 0){
    throw new Exception("Update failed!");
}

By checking the number of updated rows, you can ensure that concurrency issues are addressed appropriately.

Limitations and Considerations

While ExecuteUpdate and ExecuteDelete offer unparalleled efficiency, there are limitations to be mindful of:

• Only updating and deleting are supported; insertion requires DbSet.Add and SaveChanges().
• Retrieving original column values for affected rows is not currently supported.
• Multiple invocations cannot be batched; each call incurs a separate roundtrip to the database.

Conclusion

Incorporating ExecuteUpdate and ExecuteDelete into your EF Core 7.0 toolkit empowers you to perform database operations with unprecedented efficiency and precision. Whether streamlining deletions or orchestrating dynamic updates, these methods redefine the landscape of data manipulation in EF Core. For further insights, explore the and stay ahead in optimizing your database interactions.