How to define a concurrency property in Model-First

Question

I use Entity Framework Model-First, I want to define a column for concurrency checking. One of my property named Version, I set its Concurrency Mode to 'Fixed', type to 'Binary', 'StoreGeneratedPattern' to 'Computed'. I want the column like timestamp, every time I insert or update, the database auto-generated a value for the record.

But, when I insert records, the Version property is not nullable, so, if I don't assign it a value, the SaveChanges will not work. How can I solve it? Is my solution of creating concurrency property correct?

Thanks in advance!

You can define the column as nullable. Sql server will fill/update it anyway. — Gert Arnold, Mar 30 '12 at 14:23

score 1 · Accepted Answer · edited May 23 '17 at 10:34

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Your expectations are correct but model first default database creation workflow is not. Current model first workflow never creates timestamp columns - it uses just varbinary. To force your expected behavior you must modify the workflow which is not an easy task: here is something related to the topic.

edited May 23 '17 at 10:34

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answered Mar 30 '12 at 08:34

Ladislav Mrnka

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How to define a concurrency property in Model-First

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