Hi Oleg, This is great.
I was planning to build a .NET application similar to this as the example to my guide for the J VB.NET class. I really need to clear up my task list so I can work on thing that I love to do. ;) r/alex -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Oleg Kobchenko Sent: Friday, September 19, 2008 6:01 AM To: Programming forum Subject: [Jprogramming] JDB - subsetting result I published the JDB browser http://www.jsoftware.com/jwiki/JDB/Browser 1. Is the method there of transforming Read into boxed table optimal for using with Grid? 2. I think it would be good for such visual applications, browsing etc to have the ability to subset the result. Given a query result, but without returning it in full, there are such features of interest: * provide total number of rows in the result * return a contiguous subset given rowstart and rowcount * return every i-th row * return rows given arbitrary indices The first two are for pagination and virtual Grid. The last two are good for preview-detail graphical applications such as lens-and-chart http://www.jsoftware.com/jwiki/Addons/media/wav#viewer QDB solves this providing pseudo-column i as the result row index, so you can say "where i>20,i<40" etc. In JDB it could be a left argument to Read-family verbs, or separate verb(s). The idea is that there is Readr index, on which this subsetting can operate, before it is embodied with select columns. > From: Chris Burke <[EMAIL PROTECTED]> > > The new JDB addon is an efficient relational database written in J, see: > http://www.jsoftware.com/jwiki/JDB . > > ... ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
