Entity Framework Tutorial Delete Records
How to Bulk Delete?
Deleting entities using a custom key from file importation is a typical scenario. Despite the ChangeTracker being outstanding to track what's modified, it lacks in term of scalability and flexibility.
SaveChanges requires one database round-trip for every entity to delete. So if you need to remove 10000 entities, then 10000 database round-trips will be performed which is INSANELY slow.
StackOverflow Related Questions
Entity Framework Extensions library adds the BulkDelete extension method to the DbContext. BulkDelete offers great customization and requires the minimum database round-trips as compared to SaveChanges.
// Easy to use context.BulkDelete(list); // Easy to customize context.BulkDelete(customers, options => options.ColumnPrimaryKeyExpression = customer => customer.Code);
All rows that match the entity key are considered as existing and are DELETED from the database.
|Operations||1,000 Entities||2,000 Entities||5,000 Entities|
|SaveChange||1,000 ms||2,000 ms||5,000 ms|
|BulkDelete||45 ms||50 ms||60 ms|