Teradata – gpe TechTips

Have you ever tried to load csv data in Teradata tables? I mean: for huge files with more than a million of records we surely have to go with FastLoad, MultiLoad etc. But what about if we have a file with a few number of records and we don’t want to write FastLoad routines? Surely we’ve got the option of Teradata SQLAssistant import feature, but – as many of those who went this road will confirm – that’s not what we’d call a fast way!

That’s why I’ve decided to write a few lines of c sharp’s code to speed up the load of “not so big files”.

You can find the source code here and you’ll need Visual Studio 2017 Community Edition or higher to compile an executable version.

Also you can have a look at the main “.cs” file’s content just below.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
using Teradata.Client.Provider;
using System.Diagnostics;

namespace loadtable
{
    public partial class Form1 : Form
    {
        private  char SEPARATOR = ';';
        private string host { get; set; }
        private string uid { get; set; }
        private string pwd { get; set; }

        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Stopwatch sw = new Stopwatch();
            sw.Start();
            Teradata.Client.Provider.TdConnection mainConn = new Teradata.Client.Provider.TdConnection();
            TdConnectionStringBuilder stringBuilder = new TdConnectionStringBuilder();
            stringBuilder.CommandTimeout = 300;
            stringBuilder.ConnectionTimeout = 100;
            stringBuilder.DataSource = host;
            stringBuilder.UserId = uid;
            stringBuilder.Password = pwd;
            mainConn.ConnectionString = stringBuilder.ConnectionString;
            this.Text = host;
            mainConn.Open();


            StreamReader gperead =new StreamReader(@txtFile.Text);
            string szLine="";
            string[] szFields;
            string[] szHeader;
      
            szLine = gperead.ReadLine();
            szLine = szLine.Replace("\"", "");
            szHeader = szLine.Split(SEPARATOR);
            Teradata.Client.Provider.TdCommand gpeCmd = new Teradata.Client.Provider.TdCommand("SELECT * FROM " + cboDatabaseList.Text + "." + cboTables.Text, mainConn);
            gpeCmd.CommandTimeout = 10000;

            int counter = 0;

            Teradata.Client.Provider.TdDataAdapter gpeAdapter = new Teradata.Client.Provider.TdDataAdapter(gpeCmd);
            gpeAdapter.UpdateBatchSize = 50000;
            
            gpeAdapter.KeepCommandBatchSequence = false;
            Teradata.Client.Provider.TdCommandBuilder cb = new Teradata.Client.Provider.TdCommandBuilder(gpeAdapter);
            DataTable dt = new DataTable();
            gpeAdapter.Fill(dt);

            int iNonBlockingErrors = 0;
            while ((szLine = gperead.ReadLine()) != null) {
                szFields = szLine.Replace("\"", "").Split(SEPARATOR);

                DataRow dr = dt.NewRow();
                

                if(szFields.GetUpperBound(0)==szHeader.GetUpperBound(0)) {
                    for (int i = 0; i < szHeader.GetLength(0); i++) {
                        if (szFields[i] == "?")
                            dr[szHeader[i]] = DBNull.Value;
                        else if (dr.Table.Columns[szHeader[i]].DataType == typeof(DateTime))
                            try {
                                dr[szHeader[i]] = Convert.ToDateTime(szFields[i].Trim('\"'));
                            }
                            catch (Exception ex) {
                                dr[szHeader[i]] = DBNull.Value;
                                iNonBlockingErrors++;
                            }
                        else if (dr.Table.Columns[szHeader[i]].DataType == typeof(double))
                            dr[szHeader[i]] = Convert.ToDecimal(szFields[i].Trim('\"').Replace('.', ','));
                        else
                            try {
                                dr[szHeader[i]] = szFields[i].Trim('\"');
                            }
                            catch (Exception ex) {
                                dr[szHeader[i]] = DBNull.Value;
                                iNonBlockingErrors++;
                            }
                    }

                    dt.Rows.Add(dr);
                }



                if ((counter++ % 50000) == 0) {
                    try {
                        gpeAdapter.Update(dt);
                    }
                    catch (Exception ex) {
                        MessageBox.Show(this, ex.Message);
                    }
                    
                    textBox1.Text = (counter-1).ToString("###,###");
                }

                Application.DoEvents();
            }

            gpeAdapter.Update(dt);
            textBox1.Text = counter.ToString("###,###");

            dt.Dispose();
            gpeCmd.Dispose();
            mainConn.Close();
            mainConn.Dispose();
            gperead.Close();
            sw.Stop();
            MessageBox.Show("Done!\n" + sw.Elapsed + "\nErrors: " + iNonBlockingErrors.ToString("###,###"));
        }

        private void button2_Click(object sender, EventArgs e)
        {
            OpenFileDialog myDiag = new OpenFileDialog();

            DialogResult result = myDiag.ShowDialog();

            if (result != DialogResult.Cancel) {
                txtFile.Text = myDiag.FileName;
            }
            myDiag.Dispose();
        }

        private void populateComboes()
        {
            TdConnectionStringBuilder stringBuilder = new TdConnectionStringBuilder();
            stringBuilder.CommandTimeout = 300;
            stringBuilder.ConnectionTimeout = 100;
            stringBuilder.DataSource = host;
            stringBuilder.UserId = uid;
            stringBuilder.Password = pwd;

            using (TdConnection dbConnection = new TdConnection(stringBuilder.ConnectionString )) {
                dbConnection.Open();
                TdDataAdapter adapter = new TdDataAdapter();
                DataTable dt = new DataTable();
                TdCommand myCommand = new TdCommand("select databasename from dbc.databases", dbConnection);
                TdDataReader myReader = myCommand.ExecuteReader();
                
                while (myReader.Read()) {
                    cboDatabaseList.Items.Add(myReader[0].ToString().Trim());
                }


                myReader.Close();
                myCommand.Dispose();
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            frmLogin fLogin = new frmLogin();
            fLogin.ShowDialog(this);
            if (fLogin.fCancel)
                Application.Exit();
            else {
                host = fLogin.strHost;
                uid = fLogin.strUID;
                pwd = fLogin.strPWD;
                populateComboes();
            }
            fLogin.Dispose();
            txtSeparator.Text  = SEPARATOR.ToString();
        }

        private void cboDatabaseList_TextChanged(object sender, EventArgs e)
        {
            TdConnectionStringBuilder stringBuilder = new TdConnectionStringBuilder();
            stringBuilder.CommandTimeout = 300;
            stringBuilder.ConnectionTimeout = 100;
            stringBuilder.DataSource = host;
            stringBuilder.UserId = uid;
            stringBuilder.Password = pwd;

            using (TdConnection dbConnection = new TdConnection(stringBuilder.ConnectionString)) {
                dbConnection.Open();
                TdDataAdapter adapter = new TdDataAdapter();
                DataTable dt = new DataTable();
                TdCommand myCommand = new TdCommand("select tablename from dbc.TablesVX where databasename='" + cboDatabaseList.Text + "'", dbConnection);
                TdDataReader myReader = myCommand.ExecuteReader();

                while (myReader.Read()) {
                    cboTables.Items.Add(myReader[0].ToString().Trim());
                }


                myReader.Close();
                myCommand.Dispose();
            }
        }


        private void cmdKo_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }

        private void addColumns(string[] headers)
        {
            dgvPreview.Columns.Clear();
            for (int count = headers.GetLowerBound(0); count < headers.GetLength(0); count++)
                dgvPreview.Columns.Add(headers[count].ToString(), headers[count].ToString());
        }

        private void button3_Click(object sender, EventArgs e)
        {
            dgvPreview.Rows.Clear();
            using (FileStream file = new FileStream(txtFile.Text , FileMode.Open, FileAccess.Read, FileShare.Read, 4096)) {
                using (StreamReader reader = new StreamReader(file)) {
                    string [] headerLine= reader.ReadLine().Replace("\"","").Split(SEPARATOR);
                    addColumns(headerLine);
                    while (!reader.EndOfStream) {
                        var fields = reader.ReadLine().Replace("\"", "").Split(SEPARATOR);
                        dgvPreview.Rows.Add(fields);
                    }
                }
            }
        }
    }
}

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using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

using System.IO;

using Teradata.Client.Provider;

using System.Diagnostics;

namespace loadtable

{

public partial class Form1 : Form

{

private char SEPARATOR = ';';

private string host { get; set; }

private string uid { get; set; }

private string pwd { get; set; }

public Form1()

{

InitializeComponent();

}

private void button1_Click(object sender, EventArgs e)

{

Stopwatch sw = new Stopwatch();

sw.Start();

Teradata.Client.Provider.TdConnection mainConn = new Teradata.Client.Provider.TdConnection();

TdConnectionStringBuilder stringBuilder = new TdConnectionStringBuilder();

stringBuilder.CommandTimeout = 300;

stringBuilder.ConnectionTimeout = 100;

stringBuilder.DataSource = host;

stringBuilder.UserId = uid;

stringBuilder.Password = pwd;

mainConn.ConnectionString = stringBuilder.ConnectionString;

this.Text = host;

mainConn.Open();

StreamReader gperead =new StreamReader(@txtFile.Text);

string szLine="";

string[] szFields;

string[] szHeader;

szLine = gperead.ReadLine();

szLine = szLine.Replace("\"", "");

szHeader = szLine.Split(SEPARATOR);

Teradata.Client.Provider.TdCommand gpeCmd = new Teradata.Client.Provider.TdCommand("SELECT * FROM " + cboDatabaseList.Text + "." + cboTables.Text, mainConn);

gpeCmd.CommandTimeout = 10000;

int counter = 0;

Teradata.Client.Provider.TdDataAdapter gpeAdapter = new Teradata.Client.Provider.TdDataAdapter(gpeCmd);

gpeAdapter.UpdateBatchSize = 50000;

gpeAdapter.KeepCommandBatchSequence = false;

Teradata.Client.Provider.TdCommandBuilder cb = new Teradata.Client.Provider.TdCommandBuilder(gpeAdapter);

DataTable dt = new DataTable();

gpeAdapter.Fill(dt);

int iNonBlockingErrors = 0;

while ((szLine = gperead.ReadLine()) != null) {

szFields = szLine.Replace("\"", "").Split(SEPARATOR);

DataRow dr = dt.NewRow();

if(szFields.GetUpperBound(0)==szHeader.GetUpperBound(0)) {

for (int i = 0; i < szHeader.GetLength(0); i++) {

if (szFields[i] == "?")

dr[szHeader[i]] = DBNull.Value;

else if (dr.Table.Columns[szHeader[i]].DataType == typeof(DateTime))

try {

dr[szHeader[i]] = Convert.ToDateTime(szFields[i].Trim('\"'));

}

catch (Exception ex) {

dr[szHeader[i]] = DBNull.Value;

iNonBlockingErrors++;

}

else if (dr.Table.Columns[szHeader[i]].DataType == typeof(double))

dr[szHeader[i]] = Convert.ToDecimal(szFields[i].Trim('\"').Replace('.', ','));

else

try {

dr[szHeader[i]] = szFields[i].Trim('\"');

}

catch (Exception ex) {

dr[szHeader[i]] = DBNull.Value;

iNonBlockingErrors++;

}

dt.Rows.Add(dr);

}

if ((counter++ % 50000) == 0) {

try {

gpeAdapter.Update(dt);

}

catch (Exception ex) {

MessageBox.Show(this, ex.Message);

}

textBox1.Text = (counter-1).ToString("###,###");

}

Application.DoEvents();

}

gpeAdapter.Update(dt);

textBox1.Text = counter.ToString("###,###");

dt.Dispose();

gpeCmd.Dispose();

mainConn.Close();

mainConn.Dispose();

gperead.Close();

sw.Stop();

MessageBox.Show("Done!\n" + sw.Elapsed + "\nErrors: " + iNonBlockingErrors.ToString("###,###"));

}

private void button2_Click(object sender, EventArgs e)

{

OpenFileDialog myDiag = new OpenFileDialog();

DialogResult result = myDiag.ShowDialog();

if (result != DialogResult.Cancel) {

txtFile.Text = myDiag.FileName;

}

myDiag.Dispose();

}

private void populateComboes()

{

TdConnectionStringBuilder stringBuilder = new TdConnectionStringBuilder();

stringBuilder.CommandTimeout = 300;

stringBuilder.ConnectionTimeout = 100;

stringBuilder.DataSource = host;

stringBuilder.UserId = uid;

stringBuilder.Password = pwd;

using (TdConnection dbConnection = new TdConnection(stringBuilder.ConnectionString )) {

dbConnection.Open();

TdDataAdapter adapter = new TdDataAdapter();

DataTable dt = new DataTable();

TdCommand myCommand = new TdCommand("select databasename from dbc.databases", dbConnection);

TdDataReader myReader = myCommand.ExecuteReader();

while (myReader.Read()) {

cboDatabaseList.Items.Add(myReader[0].ToString().Trim());

}

myReader.Close();

myCommand.Dispose();

}

private void Form1_Load(object sender, EventArgs e)

{

frmLogin fLogin = new frmLogin();

fLogin.ShowDialog(this);

if (fLogin.fCancel)

Application.Exit();

else {

host = fLogin.strHost;

uid = fLogin.strUID;

pwd = fLogin.strPWD;

populateComboes();

}

fLogin.Dispose();

txtSeparator.Text = SEPARATOR.ToString();

}

private void cboDatabaseList_TextChanged(object sender, EventArgs e)

{

TdConnectionStringBuilder stringBuilder = new TdConnectionStringBuilder();

stringBuilder.CommandTimeout = 300;

stringBuilder.ConnectionTimeout = 100;

stringBuilder.DataSource = host;

stringBuilder.UserId = uid;

stringBuilder.Password = pwd;

using (TdConnection dbConnection = new TdConnection(stringBuilder.ConnectionString)) {

dbConnection.Open();

TdDataAdapter adapter = new TdDataAdapter();

DataTable dt = new DataTable();

TdCommand myCommand = new TdCommand("select tablename from dbc.TablesVX where databasename='" + cboDatabaseList.Text + "'", dbConnection);

TdDataReader myReader = myCommand.ExecuteReader();

while (myReader.Read()) {

cboTables.Items.Add(myReader[0].ToString().Trim());

}

myReader.Close();

myCommand.Dispose();

}

private void cmdKo_Click(object sender, EventArgs e)

{

Application.Exit();

}

private void addColumns(string[] headers)

{

dgvPreview.Columns.Clear();

for (int count = headers.GetLowerBound(0); count < headers.GetLength(0); count++)

dgvPreview.Columns.Add(headers[count].ToString(), headers[count].ToString());

}

private void button3_Click(object sender, EventArgs e)

{

dgvPreview.Rows.Clear();

using (FileStream file = new FileStream(txtFile.Text , FileMode.Open, FileAccess.Read, FileShare.Read, 4096)) {

using (StreamReader reader = new StreamReader(file)) {

string [] headerLine= reader.ReadLine().Replace("\"","").Split(SEPARATOR);

addColumns(headerLine);

while (!reader.EndOfStream) {

var fields = reader.ReadLine().Replace("\"", "").Split(SEPARATOR);

dgvPreview.Rows.Add(fields);

}

I’m not stating that this is an alternative to Teradata fast loading tools especially for big data files.
In no way I mean that Teradata SQLAssistant won’t work, but just that LoadData has revealed to be a bit faster (take a look at the screenshot below for an idea: 1.224.916 records in about 6 minutes).
In my experience it’s worth using LoadData for files with 1 million record max.
We’re talking of an alpha – tough fully functioning – release. There are a lot of tests the code should go under and suggestions, bug reports and enhancements are welcome!

gpe TechTips

Bear and forbear

Category: Teradata

LoadData: Populate Teradata tables