如何从OleDbCommand.ExecuteReader返回的SqlReader中提取结果

Question

我看过这篇SO post和类似的文章。我有一个更简单的问题，即获得select count(*)的结果。

我通过将它们存储在MS Access数据库中来跟踪文件名和日期。我可以通过对数据库执行select count(*)来确定我是否已经在数据库中添加了文件名和日期，如下所示：

let query = "select count(*) from ReportProcessedStatus 
                             where ReportDate = #" + report_date + "#
                             and ReportFileName = '" + fn + "'"

我的cmd.ExecuteReader ()成功，但我无法弄清楚如何从读者中获取伯爵的价值。

let reg_fnam_template = "arrgster*"

let ADOCon = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=.\Munis_To_InvoiceCloud.mdb")
    ADOCon.Open ()    

let dir_list = Directory.GetFiles(spool_dir, reg_fnam_template)

for fn in dir_list do
printfn "Working on Munis Extract File: %A " (Path.GetFileName(fn))
let query = "select count(*) from ReportProcessedStatus where ReportDate = #" + report_date + "# and ReportFileName = '" + fn + "'"
    use cmd = new OleDbCommand(query , ADOCon)
    let sql_reader = cmd.ExecuteReader ()
    let row_read_OK = sql_reader.Read ()

所有这些代码都有效，执行后row_read_OK为真。