Is there any way to specify how DLinq handles null values - for example:
[Table]
public class Thing {
string name;
[Column]
public string Name {
get { return name; }
set { name = value; }
}
}
CREATE TABLE Thing
(
Name NVARCHAR(120) NOT NULL CONSTRAINT DF_Thing_Name DEFAULT(N'No Name')
)
... results in an INSERT command that specifies NULL for [Name] when it would be helpful to indicate DEFAULT.
Using stored procedures will handle it, but something like
[Column(NullValueUpdate = NullValueUpdate.SetDefault)]
would be handy...
Thanks.
DLinq and null values and defaults
Alain Metrics
Thanks.
It would still be helpful to offer insert+refresh/update+refresh in one go for selected fields. AutoGen=true already generates 'insert... select [id]' commands. Presumably some other flag could cause other fields to be refreshed on each update/insert, thus supporting database-originated changes.
Seema
Jas001
Looking a bit further, it appears that the default DLinq behaviour is not to 'refresh' a domain object's 'columns' after inserts or updates. Permiting this behaviour would be useful when working with defaults defined in the DB.
Maybe something like:
[Column(RefreshOnUpdates = RefreshOnUpdates.Always)]
...could work.
Thanks.
PS. IMO, the existing UpdateCheck enum would be more intuitive if named ConcurrencyCheck (ditto the corresponding property on ColumnAttribute).
THizle7XU
I'm also seeing an error with context.Refresh(t, RefreshMode.KeepChanges) - I get a NullReferenceException from...
at System.Data.DLinq.CommonDataServices.Requery(Object item, Boolean clearCache)
at System.Data.DLinq.DataContext.Refresh(IEnumerable items, RefreshMode mode)
at System.Data.DLinq.DataContext.Refresh(Object item, RefreshMode mode)
I've double checked that the instance that I am passing to DataContext.Refresh() is not null.
Thanks.
ggo6
You can perform a manual refresh by using the DataContext.Refresh method, which performs a requery:
Thing t = ... // newly inserted Thing
DataContext context = ... // your data context
context.Refresh(t, RefreshMode.KeepChanges);
neo_assyrian
Of course, context.Refresh() does not sort out the original INSERT statement and handling null values and corresponding defaults in the DB - being able to request INSERT statements that do not specify NULL for null objects where DB defaults are wanted would still be handy...
Thanks.
epotter
At present, the DLinq documentation states that "AutoGen members are synchronized immediately after the data row is inserted and are available after SubmitChanges() completes."
When I add an object that looks like:
<Table Name="Address">
<Type Name="Address">
<Column Name="Id" Member="Id" Storage="id" IsIdentity="true" IsAutoGen="true" />
<Column Name="Line1" Member="Line1" Storage="line1" />
<!-- ... -->
<!-- This is supposed to mean "when the record was first saved" - it is enforced in a trigger -->
<Column Name="CreatedUtc" Member="CreatedOnData" Storage="createdOn" IsAutoGen="true" />
<Column Name="RecordVersion" Member="VersionData" Storage="version" IsVersion="true" />
</Type>
</Table>
I get a command like:
exec sp_executesql N'INSERT INTO [Address](Line1, {...}) VALUES(@p0, {...})
SELECT [t0].[Id], CONVERT(Binary,[t0].[RecordVersion]) AS [value]
FROM [Address] AS [t0]
WHERE [t0].[Id] = (CONVERT(BigInt,@@IDENTITY))',{...}
Where only the IsIdentity and IsVersion columns are refreshed and going to be "available after SubmitChanges() completes".
Regards,
Frank