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    <p>By default Entity Framework assumes that an integer primary key is database generated (equivalent to adding the attribute <code>HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity)</code> or calling <code>Property(e =&gt; e.EventID).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);</code> in the Fluent API. </p> <p>If you look at the migration that creates the table you should see this:</p> <pre><code> CreateTable( "dbo.Events", c =&gt; new { EventID = c.Int(nullable: false, identity: true), //etc }) .PrimaryKey(t =&gt; t.EventID ); </code></pre> <p>Then you changed the model using the Fluent API to <code>DatabaseGenerated.None</code>. EF puts this in the migration:</p> <pre><code>AlterColumn("dbo.Events", "EventID", c =&gt; c.Int(nullable: false, identity: false)) </code></pre> <p>And the sql generated is this:</p> <p><code>ALTER TABLE [dbo].[Events] ALTER COLUMN [EventID] [int] NOT NULL</code> </p> <p>Which actually does diddly squat. <a href="https://stackoverflow.com/questions/8230257/sql-server-remove-identity-from-a-column-in-a-table">Dropping the IDENTITY</a> from a column is not trivial. You need to drop and recreate the table or create a new column, then you have to copy the data and fix up foreign keys. So it's not surprising that EF isn't doing that for you. </p> <p>You need to work out how best to do it for yourself. You could roll back your migrations to 0 and re-scaffold from scratch now that you have specified <code>DatabaseGeneratedOption.None</code>, or you could change the migration manually to drop and recreate the table.</p> <p>Or you could drop and recreate the column:</p> <pre><code>DropColumn("Customer", "CustomerId"); AddColumn("Customer", "CustomerId", c =&gt; c.Long(nullable: false, identity: false)); </code></pre> <p><strong>EDIT</strong> Or you could <a href="http://romiller.com/2013/04/30/ef6-switching-identity-onoff-with-a-custom-migration-operation/" rel="noreferrer">Switch Identity On/Off With A Custom Migration Operation</a></p>
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    1. COThank you. I eventually managed to fix it by dropping the whole DB and letting EF create it from scratch. Now I know why it happens and that in the future I just need to drop the table.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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