I am attempting an InsertOnSubmit and it is failing since "The null value cannot be assigned to a member with type System.Int64 which is a non-nullable value type" This LINQ to SQL is driving me crazy. Please help.
The table in the SQL database has a MessageID column which is a BigInt with primary key (NOT NULL IDENTITY 1 1) no Default.
The field looks like this in the designer file to the dbml:
[global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_MessageId", AutoSync=AutoSync.OnInsert, DbType="BigInt NOT NULL IDENTITY", IsPrimaryKey=true, IsDbGenerated=true)]
public long MessageId
{
get
{
return this._MessageId;
}
set
{
if ((this._MessageId != value))
{
this.OnMessageIdChanging(value);
this.SendPropertyChanging();
this._MessageId = value;
this.SendPropertyChanged("MessageId");
this.OnMessageIdChanged();
}
}
}
So the problem is that null cannot be assigned... right. But I'm not passing null! How can I be? I'm using a long (a value type so can't be null by nature).
One workaround I found was making this field nullable but this feels like a hack since it should never be null. Anyway this just moves the problem to the ID not AutoSyncing OnInsert. (AutoSync=OnInsert is set).
Update and solution
Well it took me a while, I even posted on
stackoverflow to no avail but finally worked out the problem and wrote about it in this post about
optimistic concurrency exceptions on insert although by this time it has manifested itself in a new way since I'm using Entity Framework.
Being new to this and largely just experimenting with Silverlight for the first time wasn't 100% what to do. At least it pointed me in the right direction with its "Check web server settings" comment at the end.
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