Question

I am trying to insert multiple records into a table in one query using the MySqlCommand object in C# (using the MySQL Connector library).

The only way I know how to do this is by dynamically constructing the query myself and setting command.CommandType = CommandType.Text;

The problem with this method is that the fields are not escaped for quotes and such. I could write a function to escape the values myself I guess, but every article or question I have read on the internet appears to frown upon this, and says use command.Parameters as this more efficient and thorough.

My problem is that I don’t know how to set the parameters for multiple rows. How can I do that?

Edit: This is for a commercial service which runs 24/7, so I need to find the most efficient way to do this. I’m not using stored procedures – is this is the only way or is there another?

    public static string MySqlEscape(object value)
    {
        string val = value.ToString();
        if (val.Contains("'"))
            return val.Replace("'", "' + NCHAR(96) + '");
        else
            return val;
    }

    public void InsertProcessedData(long unprocessedID, long pagerID, long firmwareRelativeProtocolID, DataTable processedData)
    {
        using(processedData)
        {
            string paramColNames = string.Empty;
            for(int i =1;i<=processedData.Columns.Count;i+=1)
            {
                paramColNames+=string.Format("Param{0}",i);
                if(i!=processedData.Columns.Count)
                    paramColNames+=",";
            }

            string SQL = "INSERT INTO gprs_data_processed (@UnprocessedID,@PagerID,@FirmwareRelativeProtocolID,"+paramColNames+") VALUES ";

            for (int i = 0; i < processedData.Rows.Count;i+=1)
            {
                SQL += string.Format("({0},{1},{2},", unprocessedID, pagerID, firmwareRelativeProtocolID);
                for (int c = 0; c < processedData.Columns.Count; c += 1)
                {
                    SQL += string.Format("'{0}'", MySqlEscape(processedData.Rows[i][c]));
                    if (i != processedData.Columns.Count)
                        SQL += ",";
                }
                SQL+=")";
                if (i + 1 != processedData.Rows.Count)
                    SQL += ",";
                else
                    SQL += ";";
            }

            using (MySqlConnection connection = new MySqlConnection(_connection))
            {
                connection.Open();
                using (MySqlCommand command = connection.CreateCommand())
                {
                    command.CommandType = CommandType.Text;
                    command.CommandText = SQL;
                    command.ExecuteNonQuery();
                }
                connection.Close();
            }
        }
    }

Answer 1

I have ended up just using the function I have written already as it does it all in one command, and use:

public static string MySqlEscape(object value)
{
    string val = value.ToString();
    if (val.Contains("'"))
        return val.Replace("'", "''");
    else
        return val;
}

It works fine so I will see how things go.