En esta ocasión realizaremos un caso en VBnet en el cual crearemos una base de datos y una tabla donde desde un formulario de Windows Forms realice los mantenimientos respectivos.

Crear la base de datos PRACTICA2 con la tabla CLIENTES con los campos (código, nombres, apellidos, sexo), ingresar 10 clientes, programar un formulario realizar el mantenimiento de la tabla clientes.

 Creacion de la BD y la tabla Clientes
  
 USE MASTER
 CREATE DATABASE PRACTICA2
 USE PRACTICA2
  
 CREATE TABLE CLIENTES
 (
        codigo varchar(50) NOT NULL primary key,
        nombres varchar(50) NULL,
        apellidos varchar(50) NULL,
        sexo varchar(50) NULL
  )
   

  insert into CLIENTES values ('CLI001','NOELIA','GARCIA','FEMENINO');
  insert into CLIENTES values ('CLI002','FELIX','RICART','MASCULINO');
  insert into CLIENTES values ('CLI003','MARIA','OLMEDO','FEMENINO');
  insert into CLIENTES values ('CLI004','RAQUEL','GALAN','FEMENINO');
  insert into CLIENTES values ('CLI005','AURORA','SANTOS','FEMENINO');
  insert into CLIENTES values ('CLI006','RAFAEL','DOMENECH','MASCULINO');
  insert into CLIENTES values ('CLI007','RICARDO','GARCIA','MASCULINO');
  insert into CLIENTES values ('CLI008','LUIS','IRANZO','MASCULINO');
  insert into CLIENTES values ('CLI009','MARIA','RUA','FEMENINO');
  insert into CLIENTES values ('CLI010','SUSANA','LANDA','FEMENINO'); 

 Imports System.Data.SqlClient
  
 Public Class Form1
     Public cn As SqlConnection
     Public comando As SqlCommand
     Public data As SqlDataReader
  
  
     Private Sub BTNCancel_Click(sender As Object, e As EventArgs) Handles BTNCancel.Click
         Close()
  
     End Sub
  
     Private Sub BTNNuevo_Click(sender As Object, e As EventArgs) Handles BTNNuevo.Click
         limpiar()
  
     End Sub
  
     Private Sub limpiar()
         TXTApellidos.Text = ""
         TXTCodigo.Text = ""
         TXTNombres.Text = ""
         TXTSexo.Text = ""
     End Sub
  
     Private Sub BTNBuscar_Click(sender As Object, e As EventArgs) Handles BTNBuscar.Click
         Try
             cn.Open()
             comando = cn.CreateCommand()
             comando.CommandText = "select *from CLIENTES where codigo='" + TXTCodigo.Text + "'"
             data = comando.ExecuteReader()
             If (data.Read) Then
                 TXTCodigo.Text = data(0)
                 TXTNombres.Text = data(1)
                 TXTApellidos.Text = data(2)
                 TXTSexo.Text = data(3)
             End If
             cn.Close()
  
         Catch ex As Exception
  
         End Try
     End Sub
  
     Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
         cn = New SqlConnection("Data Source=.;Initial Catalog=PRACTICA2;Integrated Security=True")
     End Sub
  
     Private Sub BTNGuardar_Click(sender As Object, e As EventArgs) Handles BTNGuardar.Click
         Try
             cn.Open()
             comando = cn.CreateCommand()
             comando.CommandText = "insert into CLIENTES values ('" + TXTCodigo.Text + "','" + TXTNombres.Text + "','" + TXTApellidos.Text + "','" + TXTSexo.Text + "')"
             comando.ExecuteNonQuery()
             MsgBox("Registro ingresado correctamente")
             cn.Close()
             limpiar()
         Catch ex As Exception
  
         End Try
     End Sub
  
     Private Sub BTNEliminar_Click(sender As Object, e As EventArgs) Handles BTNEliminar.Click
         Try
             cn.Open()
             comando = cn.CreateCommand()
             comando.CommandText = "delete from CLIENTES where codigo='" + TXTCodigo.Text + "'"
             comando.ExecuteNonQuery()
             MsgBox("Registro eliminado correctamente")
             cn.Close()
             limpiar()
         Catch ex As Exception
  
         End Try
     End Sub
  
     Private Sub BTNEditar_Click(sender As Object, e As EventArgs) Handles BTNEditar.Click
         Try
             cn.Open()
             comando = cn.CreateCommand()
             comando.CommandText = "update CLIENTES SET nombres='" + TXTNombres.Text + "',apellidos='" + TXTApellidos.Text + "',sexo='" + TXTSexo.Text + "' where codigo='" + TXTCodigo.Text + "'"
             comando.ExecuteNonQuery()
             MsgBox("Registro actualizado correctamente")
             cn.Close()
             limpiar()
  
         Catch ex As Exception
  
         End Try
     End Sub
 End Class