Article View: borland.public.cppbuilder.database.multi-tier
Article #240Weird MIDAS/DataSnap behavior...
From: mr_organic
Date: Wed, 29 Dec 2004 16:41
Date: Wed, 29 Dec 2004 16:41
37 lines
2285 bytes
2285 bytes
Hello all,
We have a legacy app that was created with C++Builder 5 and used MIDAS to
communicate with an MTS/COM+ middle-tier component. We had to build a
completely stateless client because our server was atually part of a
cluster and we had to be able to fail over to any of the machines in the
cluster.
We used a lot of code like this (assume that "dc" is the DCOMConnection
component):
dc->Open();
cdsFoo->Close();
cdsFoo->Params->ParamValues["some_key"] = SomeValue;
cdsFoo->Open();
dc->Close();
This code worked just fine in BCB5. However, we have been trying to
upgrade to BCB6 and I have discovered that this no longer works! The
client dataset just keeps fetching the initial records over and over
again, regardless of what you change the parameter to in successive
queries. I remember talking to Borland about this when BCB6 first came
out, but we have just applied the Patch #4, and the problem remains.
I have verified that if we maintain a stateful connection (i.e., always-
on) to the server, the retrieves work as expected. It's only in this
"disconnected" model that the problem appears.
My question is: is this a bug in MIDAS/DataSnap, or is DataSnap
*supposed* to be stateful regarding an "always-on" connection to the
middle-tier? If it *is* a bug, is Borland planning to fix it?
Any info would be greatly appreciated.
Thanks,
mr_organic
Technical Details
Message-ID:
<41d2de1e$1@newsgroups.borland.com>Path:
arc1-ca.pugleaf.net!g2news1.google.com!news2.google.com!proxad.net!213.200.89.82.MISMATCH!tiscali!newsfeed1.ip.tiscali.net!border2.nntp.ams.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!pe2.news.blueyonder.co.uk!blueyonder!news-peer-test!btnet!newsfeed.bt.es!caladan.landsraad.net!newsgroups.borland.com!not-for-mailShow Full Headers
Complete Article Headers
X-Google-Thread: fcd2b,6ec8620b19e35c76,start X-Google-Attributes: gidfcd2b,public X-Google-Language: ENGLISH,ASCII-7-bit Newsgroups: borland.public.cppbuilder.database.multi-tier Subject: Weird MIDAS/DataSnap behavior... From: "mr_organic" <mr_organic@yourmamashouse.com> User-Agent: Xnews/5.04.25 NNTP-Posting-Host: 129.176.197.15 Message-ID: <41d2de1e$1@newsgroups.borland.com> Date: 29 Dec 2004 08:41:02 -0800 X-Trace: newsgroups.borland.com 1104338462 129.176.197.15 (29 Dec 2004 08:41:02 -0800) Lines: 37 Path: arc1-ca.pugleaf.net!g2news1.google.com!news2.google.com!proxad.net!213.200.89.82.MISMATCH!tiscali!newsfeed1.ip.tiscali.net!border2.nntp.ams.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!pe2.news.blueyonder.co.uk!blueyonder!news-peer-test!btnet!newsfeed.bt.es!caladan.landsraad.net!newsgroups.borland.com!not-for-mail