This is an old post but became my problem, so posting what worked for me here for others’ benefit.
You seem to be hoping to collect all rows where the value in [Delivered Qty] is BLANK? For that you’ll want to remove the equals sign and single quotes; and replace with is null.
FileDt.Select(“[Delivered Qty] is null”).CopyToDataTable
If you were supplying your Select statement with a date (may work with numbers too, maybe?), that solution is hidden in Mateus’ answer (https://forum.uipath.com/t/filter-datatable-contains-datetime/55867/3:
those values need hashtags added around the value in order to properly read in as a double instead of string.
(in an Assign activity): ArchiveDate = DateTime.Now.AddDays(-14).ToShortDateString // This is whatever date was two weeks ago from today, and the Select syntax looks like:
FileDt.Select(“[Delivery Date] >= #”+ArchiveDate+“#”).CopyToDataTable