Function GETPMAX(SID As String) As String

    Dim result As String

    '链接数据库

    Set Cnn = CreateObject("ADODB.Connection")

    Set rt = CreateObject("ADODB.Recordset")

    Cnn.ConnectionString = "Provider = SQLOLEDB;User ID= ;password=;Data Source=;Initial Catalog = "

    Cnn.Open

    Sql = "SELECT TOP 1 Pmax FROM dbo where ID='" & SID & "' order by hDateTime desc"

     '获取记录集

    Set rt = Cnn.Execute(Sql)

     '根据字段获取值

    result = CStr(rt("Pmax"))

    GETPMAX = result

    '关闭记录集

    rt.Close

    '关闭数据库链接,释放资源

    Cnn.Close

End Function