How to pass table value parameters to stored procedure from .net code

Question

I have a SQL Server 2005 database. In a few procedures I have table parameters that I pass to a stored proc as an nvarchar (separated by commas) and internally

Answer 1

Generic

   public static DataTable ToTableValuedParameter<T, TProperty>(this IEnumerable<T> list, Func<T, TProperty> selector)
    {
        var tbl = new DataTable();
        tbl.Columns.Add("Id", typeof(T));

        foreach (var item in list)
        {
            tbl.Rows.Add(selector.Invoke(item));

        }

        return tbl;

    }

Answer 2

Use this code to create suitable parameter from your type:

private SqlParameter GenerateTypedParameter(string name, object typedParameter)
{
    DataTable dt = new DataTable();

    var properties = typedParameter.GetType().GetProperties().ToList();
    properties.ForEach(p =>
    {
        dt.Columns.Add(p.Name, Nullable.GetUnderlyingType(p.PropertyType) ?? p.PropertyType);
    });
    var row = dt.NewRow();
    properties.ForEach(p => { row[p.Name] = (p.GetValue(typedParameter) ?? DBNull.Value); });
    dt.Rows.Add(row);

    return new SqlParameter
    {
        Direction = ParameterDirection.Input,
        ParameterName = name,
        Value = dt,
        SqlDbType = SqlDbType.Structured
    };
}

Answer 3

DataTable, DbDataReader, or IEnumerable<SqlDataRecord> objects can be used to populate a table-valued parameter per the MSDN article Table-Valued Parameters in SQL Server 2008 (ADO.NET).

The following example illustrates using either a DataTable or an IEnumerable<SqlDataRecord>:

SQL Code:

CREATE TABLE dbo.PageView
(
    PageViewID BIGINT NOT NULL CONSTRAINT pkPageView PRIMARY KEY CLUSTERED,
    PageViewCount BIGINT NOT NULL
);
CREATE TYPE dbo.PageViewTableType AS TABLE
(
    PageViewID BIGINT NOT NULL
);
CREATE PROCEDURE dbo.procMergePageView
    @Display dbo.PageViewTableType READONLY
AS
BEGIN
    MERGE INTO dbo.PageView AS T
    USING @Display AS S
    ON T.PageViewID = S.PageViewID
    WHEN MATCHED THEN UPDATE SET T.PageViewCount = T.PageViewCount + 1
    WHEN NOT MATCHED THEN INSERT VALUES(S.PageViewID, 1);
END

C# Code:

private static void ExecuteProcedure(bool useDataTable, 
                                     string connectionString, 
                                     IEnumerable<long> ids) 
{
    using (SqlConnection connection = new SqlConnection(connectionString)) 
    {
        connection.Open();
        using (SqlCommand command = connection.CreateCommand()) 
        {
            command.CommandText = "dbo.procMergePageView";
            command.CommandType = CommandType.StoredProcedure;

            SqlParameter parameter;
            if (useDataTable) {
                parameter = command.Parameters
                              .AddWithValue("@Display", CreateDataTable(ids));
            }
            else 
            {
                parameter = command.Parameters
                              .AddWithValue("@Display", CreateSqlDataRecords(ids));
            }
            parameter.SqlDbType = SqlDbType.Structured;
            parameter.TypeName = "dbo.PageViewTableType";

            command.ExecuteNonQuery();
        }
    }
}

private static DataTable CreateDataTable(IEnumerable<long> ids) 
{
    DataTable table = new DataTable();
    table.Columns.Add("ID", typeof(long));
    foreach (long id in ids) 
    {
        table.Rows.Add(id);
    }
    return table;
}

private static IEnumerable<SqlDataRecord> CreateSqlDataRecords(IEnumerable<long> ids) 
{
    SqlMetaData[] metaData = new SqlMetaData[1];
    metaData[0] = new SqlMetaData("ID", SqlDbType.BigInt);
    SqlDataRecord record = new SqlDataRecord(metaData);
    foreach (long id in ids) 
    {
        record.SetInt64(0, id);
        yield return record;
    }
}

Answer 4

The cleanest way to work with it. Assuming your table is a list of integers called "dbo.tvp_Int" (Customize for your own table type)

Create this extension method...

public static void AddWithValue_Tvp_Int(this SqlParameterCollection paramCollection, string parameterName, List<int> data)
{
   if(paramCollection != null)
   {
       var p = paramCollection.Add(parameterName, SqlDbType.Structured);
       p.TypeName = "dbo.tvp_Int";
       DataTable _dt = new DataTable() {Columns = {"Value"}};
       data.ForEach(value => _dt.Rows.Add(value));
       p.Value = _dt;
   }
}

Now you can add a table valued parameter in one line anywhere simply by doing this:

cmd.Parameters.AddWithValueFor_Tvp_Int("@IDValues", listOfIds);

Answer 5

Further to Ryan's answer you will also need to set the DataColumn's Ordinal property if you are dealing with a table-valued parameter with multiple columns whose ordinals are not in alphabetical order.

As an example, if you have the following table value that is used as a parameter in SQL:

CREATE TYPE NodeFilter AS TABLE (
  ID int not null
  Code nvarchar(10) not null,
);

You would need to order your columns as such in C#:

table.Columns["ID"].SetOrdinal(0);
// this also bumps Code to ordinal of 1
// if you have more than 2 cols then you would need to set more ordinals

If you fail to do this you will get a parse error, failed to convert nvarchar to int.