Entity Framework Extensions Use Custom Column

Problem

You want to perform a Bulk Operation (BulkInsert, BulkUpdate, BulkDelete, or BulkMerge) but only on some specific columns.

For example, you want to perform a BulkUpdate on a customer list but only UPDATE the name and email properties.

Solution

You can specify the column on which the operation should be performed with the ColumnInputExpression options.

Example

// DON'T add the key if auto-generated
ctx.BulkInsert(customers, operation => operation.ColumnInputExpression =
    customer => new {customer.Name, customer.Email});

// ALWAYS add the key
ctx.BulkUpdate(customers, operation => operation.ColumnInputExpression =
    customer => new { customer.ID, customer.Name, customer.Email });

// ALWAYS add the key
ctx.BulkMerge(customers, operation => operation.ColumnInputExpression =
    customer => new {customer.ID, customer.Name, customer.Email});

Troubleshooting

INSERT + Destination mapped more than once error

You receive the following error:

One of your columns has a destination mapped more than once. See the inner exception for details.

Make sure the key has not been added to the ColumnInputExpression.

UPDATE or MERGE + No primary found

You receive the following error:

An error occurred, no primary could be found or resolved.

Make sure the key has been added to the ColumnInputExpression.