(SQL2010)如何编写选择最小未使用数字的VB.NET查询

Imports System.Data.SqlClient

Public Class Form1
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim connectionString As String = "Data Source=YourServer;Initial Catalog=YourDatabase;User ID=YourUsername;Password=YourPassword"
        Dim query As String = "SELECT MIN(number) + 1 AS smallestNumber FROM YourTable WHERE number + 1 NOT IN (SELECT number FROM YourTable)"

        Using connection As New SqlConnection(connectionString)
            connection.Open()

            Using command As New SqlCommand(query, connection)
                Using reader As SqlDataReader = command.ExecuteReader()
                    If reader.Read() Then
                        Dim smallestNumber As Integer = reader.GetInt32(0)
                        MessageBox.Show("The smallest unused number is: " & smallestNumber.ToString())
                    Else
                        MessageBox.Show("No unused numbers found.")
                    End If
                End Using
            End Using

            connection.Close()
        End Using
    End Sub
End Class