Xref: utzoo comp.databases:2856 comp.sys.ibm.pc:30865 comp.dcom.lans:3083
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!ucdavis!ic2020!jim
From: jim@ic2020.UUCP (Jim Carter)
Newsgroups: comp.databases,comp.sys.ibm.pc,comp.dcom.lans
Subject: Re: Concurrency Control + Question
Message-ID: <221@ic2020.UUCP>
Date: 30 Jun 89 14:06:25 GMT
References: <25232@shemp.CS.UCLA.EDU>
Lines: 38

in article <25232@shemp.CS.UCLA.EDU>, gblee@maui.cs.ucla.edu says:
> 
> Please consider the following problems: ...

We have a similar problem, which we have basically solved the problem by
using xenix and foxbase+.  If you are using dbase3+, I beleive you have the
same record/file locking available to you.  The record locking available
in sco foxbase+ is quite nice.  I have no idea what effects this would 
have on your network system.  It has very little effect on our system.
As far as paradox, Never used it but I would think the record/file locking
is similar in use.

The simple foxbase+ code to lock and edit a record is 

	find name       && lookup the correct record.
	if rlock()      && returns true if record lock successfull.
		edit          && edit this record. ( or modify somehow )
		unlock()      && unlock all locks you have set
	else
		... display message, that you can not lock this record.
	endif

MY QUESTION: 
The only problem I have had is on some operations that could effect ALL 
records, Exclusive access is required.  I have not found a simple way
to gain exclusive access.  Anyone have a simple solution ?

> Don't simply say you have to buy expensive Distributed DBMS or Minicomputer.
> What is the constsructive solution for this problem? 

As far as constructive solution, my experience has shown that you do get 
what you pay for in the concurency area.  I do think a larger system is
better in the long run, but your network will do the job.

> --Geunbae Lee,m UCLA-CS-AI.
-- 
Jim Carter (Sequoia Contact Lens,1355 11th Street,Reedley,CA,93654)
{...!csufres!csuf3b!ic2020!jim} 209/638-3939, Fax 209/638-5433