.NET: How to insert XML document into SQL Server

Question

I want to insert arbitrary XML into SQL Server. The XML is contained in an XmlDocument object.

The column I want to insert into is either nvarchar

Answer 1

Just wanted to add an SQLConnection equivalent to Jonathan Overholt's solution:

private void StoreXMLInDatabase(XmlDocument doc)
{
    // xmlvalue is the name of the database column you want to insert into
    String sql = "INSERT INTO [tablename] (xmlvalue) VALUES (@xmlvalue)";
    // In order to read out you connection string from app.config, remember first to add a reference to System.Configuration in references,
    // and set using System.Configuration; in the top of the file
    string connString = ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString;  
    using (SqlConnection conn = new SqlConnection(connString))
    {
        if (conn.State == ConnectionState.Closed)
        {
            conn.Open();
        }
        SqlTransaction transaction = conn.BeginTransaction();
        try
        {
            // Remember to specify the SqlTransaction *name* (transaction)
            SqlCommand cobj = new SqlCommand(sql, conn, transaction);
            cobj.CommandText = sql;
            cobj.Parameters.AddWithValue("xmlvalue", new SqlXml(new XmlNodeReader(doc)));
            cobj.ExecuteNonQuery();
            transaction.Commit();
        }
        catch (SqlException ex)
        {
            //2627 = inserting duplicate key fail. Lets the procedure continue although an identity insert fail occurs
            if (ex.Number == 2627)
            {
                transaction.Rollback();
            }
        }
    } // end using
}

Tested OK in Visual studio 2017 and 2013 with .net up to version 4.6.2, and against MS SQL Server 2008 R2, 2012 and 2016

If an identity insert fail and you want to stop the procedure then, just insert a line after transaction.Rollback() like this:

throw;

Or you can stop the procedure in any circumstance by putting the transaction.Rollback(); and throw; lines just outside the conditional (the if)