Option Explicit On
Option Strict On
Imports System
Imports System.Data
Imports System.Data.OleDb

Public Class Form1
    'строка подключения
    Dim connectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\БД.mdb;User Id=admin;Password=;"
    Dim queryString As String
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        'Перебор всех записей
        queryString = "SELECT * from t1"
        Using connection As New OleDbConnection(connectionString)
            Dim command As New OleDbCommand(queryString, connection)
            Try
                connection.Open()
                Dim dataReader As OleDbDataReader = command.ExecuteReader()
                Do While dataReader.Read()
                    MsgBox(CStr(dataReader(1)) & "/" & CStr(dataReader(2)) & "/" & CStr(dataReader(3)))
                Loop
                dataReader.Close()
            Catch ex As Exception
            End Try
        End Using
    End Sub
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        'Вывод тех у кого возраст > 10
        Dim queryString As String = _
        "SELECT id, fam, ima, vozr, nac from t1 " _
        & "WHERE vozr > ? " _
        & "ORDER BY vozr DESC;"
        Dim paramValue As Integer = 10
        Using connection As New OleDbConnection(connectionString)
            Dim command As New OleDbCommand(queryString, connection)
            command.Parameters.AddWithValue("@vozr_val", paramValue)
            Try
                connection.Open()
                Dim dataReader As OleDbDataReader = command.ExecuteReader()
                Do While dataReader.Read()
                    MsgBox(CStr(dataReader(1)) & "/" & CStr(dataReader(2)) & "/" & CStr(dataReader(3)))
                Loop
                dataReader.Close()
            Catch ex As Exception
            End Try
        End Using
    End Sub
End Class