Bulk Merge (Enterprise Feature)
MERGE all entities from the database.
A merge is an
UPSERT operation. All rows that match the entity key are considered as existing and are
UPDATED, other rows are considered as new rows and are
INSERTED in the database.
This feature is provided by Z.EntityFramework.Extensions that's used by more than 2000 customers all over the world.
// Easy to use ctx.BulkMerge(list); // Easy to customize context.BulkMerge(customers, options => options.ColumnPrimaryKeyExpression = customer => customer.Code);
Merging entities using a custom key from file importation is a typical scenario.
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
update. So if you need to
update 10000 entities, then 10000 database round-trips will be performed which is INSANELY slow.
BulkMerge in counterpart offers great customization and requires the minimum database round-trips as possible.
|Operations||1,000 Entities||2,000 Entities||5,000 Entities|
|SaveChanges||1,000 ms||2,000 ms||5,000 ms|
|BulkMerge||65 ms||80 ms||110 ms|