DataTable.Copy getting error - cannot find relation 0

Question

User-893002196 posted

Hi All,

I try to copy all the dataTable with data to another new dataTable and trying to remove the column if type = object as below:-

 public static void bulkCopyIntoTable(DataTable dtData, string sDatabaseTableName, string sConnectionString)
        {
            
                DataTable dtDatas = new DataTable();
                dtData.DataSet.EnforceConstraints = false;
                dtDatas = dtData.Copy();  << Getting error as below
                dtData.DataSet.EnforceConstraints = true;
                dtDatas.Constraints.Add("PK_"+dtData.Columns[0].ColumnName, dtData.Columns[0], true);

                for (int i = 0; i < dtDatas.Columns.Count; i++)
                {
                    if (dtDatas.Columns[i].DataType.ToString().Contains("System.Object"))
                    {
                        var names = dtDatas.Columns[i].ColumnName;
                        dtDatas.Columns.Remove(names);
                    }
                }

But, I getting error:

cannot find relation 0

Please advise,

Thank you.

Regards,

Micheale

Answer 1

User-271186128 posted

Hi micnie2020,

According to your code and description, it seems the issue is not related to the DataTable.Copy() Method. I have written a sample using the DataTable.Copy Method, and it worked well on my side. So, I would like to suggest you check your code to see if there is anything breaking. I suggest you set a breakpoints to check whether the tdData is empty or not. The following is the sample what I did, you could refer to it:

        protected void Page_Load(object sender, EventArgs e)
        {
            GetDataTable();
        }

        protected void GetDataTable()
        {
            DataSet ds = new DataSet();
            DataTable dt = new DataTable();
            ds.Tables.Add(dt);
            string constr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;

            //Here I use NorthWind Database and I test the table Orders and Order Details, and they all worked well
            string query = "select * from [Order Details]";
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand(query))
                {
                    using (SqlDataAdapter da = new SqlDataAdapter())
                    {
                        cmd.CommandType = CommandType.Text;
                        cmd.Connection = con;
                        da.SelectCommand = cmd;
                        da.Fill(dt);
                    }
                }
            }
            dt.DataSet.EnforceConstraints = false;
            DataTable dt2 = new DataTable();
            dt2 = dt.Copy();

            GridView1.DataSource = dt2;
            GridView1.DataBind();
        }

If you have any other question, please feel free to ask.

Best Regards,
Dillion