Question

I have a stored procedure to handle Inserts, Updates and Deletes to a table defined as

CREATE TABLE [dbo].[TestTable](
    [Id] [int] PRIMARY KEY NOT NULL,
    [Data] [nvarchar](50) NOT NULL,
    [ChangeDate] [datetime] NULL)

with the stored prodedure

CREATE PROCEDURE MergeTest
    @Testing TestTableType readonly
AS
BEGIN
    MERGE INTO Testing as Target
    USING (SELECT * FROM @Testing) AS SOURCE
        ON (Target.Id = Source.Id)
    WHEN MATCHED THEN
        UPDATE SET 
            Target.Data = Source.Data,
            Target.ChangeDate = Source.ChangeDate
    WHEN NOT MATCHED BY TARGET THEN
        INSERT (Data, ChangeDate)
        VALUES (Source.Data, Source.ChangeDate)
    WHEN NOT MATCHED BY SOURCE THEN
        DELETE;

    RETURN 0;
END

and the UDT Type as

CREATE TYPE TestTableType AS TABLE(
    [Id] [int] PRIMARY KEY NOT NULL,
    [Data] [nvarchar](50) NOT NULL,
    [ChangeDate] [datetime] NULL)

I am trying to use this structure to do bulk inserts, etc from C#. Using the following code it works:

using (SqlConnection connection = new SqlConnection(@"..."))
{
    connection.Open();

    DataTable DT = new DataTable();
    DT.Columns.Add("Id", typeof(int));
    DT.Columns.Add("Data", typeof(string));
    DT.Columns.Add("ChangeDate", typeof(DateTime));

    for (int i = 0; i < 100000; i++)
    {
        DT.AddTestRow((i + 1), (i + 1).ToString(), DateTime.Now);
    }

    using (SqlCommand command = new SqlCommand("MergeTest", connection))
    {
        command.CommandType = CommandType.StoredProcedure;
        command.Parameters.AddWithValue("@Testing", DT);
        command.ExecuteNonQuery();
    }
}

However, when i change the lines

DataTable DT = new DataTable();
DT.Columns.Add("Id", typeof(int));
DT.Columns.Add("Data", typeof(string));
DT.Columns.Add("ChangeDate", typeof(DateTime));

to

DataSet1.TestDataTable DT = new DataSet1.TestDataTable();

which is a strongly typed version of the same DataTable structure I get a Argument Exception Error of

No mapping exists from object type TestBulkInsertDataset.DataSet1+TestDataTable to a known managed provider native type.

Is there any way to use a strongly typed DataTable as a User Defined Table Type Parameter?

Answer 1

Found the answer. When using strongly typed Data Tables you have to specify the type for the parameter. The parameter line becomes:

var testingparam = command.Parameters.AddWithValue("@Testing", DT);
testingparam.SqlDbType = SqlDbType.Structured;

and then it all works.