update query not working vb net

Question

When I try to update the database using the following query, I receive the message "update successful" , but it's not true, my data is still the same as before.

Public Function alterar() As Boolean
    Dim cd As New npgSqlCommand
    Dim query As String = ""

    Try
       query &= "UPDATE [Caixa] SET Recibo = '" & iRecibo & "' ,  CentroCusto = '" & sCentroCusto & "' ,  Data = '" & sData & "' , Dia = '" & sDia & "' , _
       Mes ='" & sMes & "', Ano = '" & sAno & "' , CentroCustoResumo = '" & sCentroCustoResumo & "' , CodSubCentroCusto ='" & sCodSubCentroCusto & "', _
        DescSubCentroCusto ='" & sDescSubCentroCusto & "', Eventos ='" & sEventos & "', Historico = '" & sHistorico & "' , _
       Dinheiro = '" & sDinheiro & "', Cheque = '" & sCheque & "', Cartao = '" & sCartao & "', DepositoDireto = '" & sDepositoDireto & "', _
       Total ='" & sTotal &  "' WHERE Recibo = '" & iRecibo.ToString()

        If Conexao.NonQuery(cd) Then
            sStatus = "O Recibo " & iRecibo & " foi alterado com sucesso!"
            Return True
        End If
    Catch ex As Exception
        sStatus = ex.Message
    End Try
    Return True
End Function

Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
    Dim c As New Caixa()
    Try
        If TextBox1.Text <> "" Then
            c.Recibo = CInt(TextBox1.Text)

            If c.excluir() Then
                MessageBox.Show(c.Status)
                CaixaLoad()
            Else
                MessageBox.Show(c.Status)
            End If
        Else
            MessageBox.Show("Nenhum registro selecionado!")
        End If
    Catch ex As Exception
        'MessageBox.Show(ex.Message)
    End Try
End Sub

What's the problem with my query?

Answer 1

Fixing your code

Try the following code, (1) i used cmd.ExecuteNonQuery() instead of Conexao.NonQuery(cd) also (2) the query string was not assigned to cmd command, and (3) [] brackets are not used in postgresql you have to use double quotes if needed. (4) it is recommended to use Using when working with npgsqlcommand Class

Public Function alterar() As Boolean

    Dim query As String = ""
    Try

       query = "UPDATE Caixa SET Recibo = '" & iRecibo & "' ,  CentroCusto = '" & sCentroCusto & "' ,  Data = '" & sData & "' , Dia = '" & sDia & "' , " &  _
       "Mes ='" & sMes & "', Ano = '" & sAno & "' , CentroCustoResumo = '" & sCentroCustoResumo & "' , CodSubCentroCusto ='" & sCodSubCentroCusto & "', " &  _
       "DescSubCentroCusto ='" & sDescSubCentroCusto & "', Eventos ='" & sEventos & "', Historico = '" & sHistorico & "' , " & _
       "Dinheiro = '" & sDinheiro & "', Cheque = '" & sCheque & "', Cartao = '" & sCartao & "', DepositoDireto = '" & sDepositoDireto & "', " & _
       "Total ='" & sTotal &  "' WHERE Recibo = '" & iRecibo.ToString & "'"

        Using cmd As New npgSqlCommand

            cmd.CommandText = query
            cmd.Connection = conn 

            cmd.ExecuteNonQuery()
            sStatus = "O Recibo " & iRecibo & " foi alterado com sucesso!"

        End Using

        Return True



    Catch ex As Exception
        sStatus = ex.Message
        Return False
    End Try

End Function

Parameterized query

it is recommended to use parameterized queries for better security (more secure against sql injection) and better performance, you can follow these similar question for more information:

• Update command using Npgsql postgres and C#

References

• Npgsql Documentation
• Quoting columns with spaces in PostgreSQL?