Links Beitreten Mysql Abfrage Ergebnis falsch

Question

Ich habe eine mysql Links Join-Abfrage. Diese Abfrage wird ausgeführt. Aber die linke beigefügte Tabelle erhält keine Werte. Bitte gehen Sie durch die Abfrage unten. Ich arbeite in C#

void getstuinfo() 
     { 
      try 
      { 
       MySqlCommand com = new MySqlCommand("select stumaster.stuname,"+ 
       "stumaster.lname,"+ 
       "stumaster.fname,"+ 
       "stumaster.mname,"+ 
       "stumaster.fa_calty,"+ 
       "stumaster.sex,"+ 
       "castmaster.castdisp,"+ 
       "stumaster.castcode,"+ 
       "stumaster.nwscs "+ 
       "from stumaster "+ 
       " left join castmaster on stumaster.castcode = castmaster.castcode "+ 
       " where grno = " + Convert.ToInt32(textBox1.Text).ToString(), con_db.con); 
       MySqlDataReader dr1 = com.ExecuteReader(); 
       if (dr1.HasRows) 
       { 
        while (dr1.Read()) 
        { 
         textBox2.Text = (dr1[("stuname")].ToString()); 
         textBox4.Text = (dr1["lname"]).ToString(); 
         textBox5.Text = (dr1["fname"]).ToString(); 
         textBox6.Text = (dr1["mname"]).ToString(); 
         comboBox5.Text = (dr1["fa_calty"]).ToString(); 
         comboBox1.Text = (dr1["castdisp"]).ToString(); 
         textBox7.Text = (dr1["castcode"]).ToString(); 
         textBox9.Text = (dr1["nwscs"]).ToString(); 
         string wsex = (dr1["sex"]).ToString(); 

         if (wsex == "M") 
         { 
          radioButton1.Checked = true; 
         } 
         else 
         { 
          radioButton2.Checked = true; 
         } 
        } 
        dr1.Close(); 
       } 
       else 
       { 
        MessageBox.Show("Not a Valid G.R.No.", " Student Information "); 
        dr1.Close(); 
        textBox1.Focus(); 
        return; 
       } 
      } 
      catch (FormatException) 
      { 
       MessageBox.Show("Date is Invalid "); 
      } 
     } 

Answer 1

Sie den Tabellennamen mit GRNO

dh

stumaster.grno = conditiion