[RESOLVED] SQL command error

[GideonE]

I have the following VB.NET code :

Dim kode As String = ""
        Dim beskrywing As String = ""
 
 
        If Me.SlaagCheckBox.Checked = True Then
          
            kode = kode & "GrSl"
            beskrywing = beskrywing & "Slaag"
 
            opdragskepkode.Connection = konneksie
            opdragskepkode.CommandText = "UPDATE skedulering2 " &
                                    "SET GroeperingsKode        = CONCAT( ''," & kode & ") , " &
                                    "GroepperingsBeskrywing     = CONCAT( ''," & beskrywing & ") ;"
      
 
 
            opdragskepkode.ExecuteNonQuery()
        
        End If

When I run my application I get the following error : Invalid column name 'Slaag'.

For the life of me I cannot see my mistake. Any help would be much appreciated.