Question

I’m trying to send a DataTable to a stored procedure using c#, .net 2.0 and SQLServer 2012 Express.

This is roughly what I’m doing:

        //define the DataTable
        var accountIdTable = new DataTable("[dbo].[TypeAccountIdTable]");

        //define the column
        var dataColumn = new DataColumn {ColumnName = "[ID]", DataType = typeof (Guid)};

        //add column to dataTable
        accountIdTable.Columns.Add(dataColumn);

        //feed it with the unique contact ids
        foreach (var uniqueId in uniqueIds)
        {
            accountIdTable.Rows.Add(uniqueId);
        }

        using (var sqlCmd = new SqlCommand())
        {
            //define command details
            sqlCmd.CommandType = CommandType.StoredProcedure;
            sqlCmd.CommandText = "[dbo].[msp_Get_Many_Profiles]";
            sqlCmd.Connection = dbConn; //an open database connection

            //define parameter
            var sqlParam = new SqlParameter();
            sqlParam.ParameterName = "@tvp_account_id_list";
            sqlParam.SqlDbType = SqlDbType.Structured;
            sqlParam.Value = accountIdTable;

            //add parameter to command
            sqlCmd.Parameters.Add(sqlParam);

            //execute procedure
            rResult = sqlCmd.ExecuteReader();

            //print results
            while (rResult.Read())
            {
                PrintRowData(rResult);
            }
        }

But then I get the following error:

ArgumentOutOfRangeException: No mapping exists from SqlDbType Structured to a known DbType.
Parameter name: SqlDbType

Upon investigating further (in MSDN, SO and other places) it appears as if .net 2.0 does not support sending a DataTable to the database (missing things such as SqlParameter.TypeName), but I’m still not sure since I haven’t seen anyone explicitly claiming that this feature is not available in .net 2.0

Is this true?

If so, is there another way to send a collection of data to the database?

Thanks in advance!

Answer 1

Out of the box, ADO.NET does not suport this with good reason. A DataTable could take just about any number of columns, which may or may not map up to a real table in your database.

If I’m understanding what you want to do – upload the contents of a DataTable quickly to a pre-defined, real table with the same structure, I’d suggest you investigate SQLBulkCopy.

From the documentation:

Microsoft SQL Server includes a popular command-prompt utility named
bcp for moving data from one table to another, whether on a single
server or between servers. The SqlBulkCopy class lets you write
managed code solutions that provide similar functionality. There are
other ways to load data into a SQL Server table (INSERT statements,
for example), but SqlBulkCopy offers a significant performance
advantage over them.

The SqlBulkCopy class can be used to write data only to SQL Server
tables. However, the data source is not limited to SQL Server; any
data source can be used, as long as the data can be loaded to a
DataTable instance or read with a IDataReader instance.

SqlBulkCopy will fail when bulk loading a DataTable column of type
SqlDateTime into a SQL Server column whose type is one of the
date/time types added in SQL Server 2008.

However, you can define Table Value Parameters in SQL Server in later versions, and use that to send a Table (DateTable) in the method you’re asking. There’s an example at http://sqlwithmanoj.wordpress.com/2012/09/10/passing-multipledynamic-values-to-stored-procedures-functions-part4-by-using-tvp/