From: Stephen B. <st...@cf...> - 2002-06-17 01:33:06
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On June 15, 2002 1:16 PM "David Essex" <de...@ar...> wrote: <snip> > > Berkeley DB maybe overkill, and ISAM maybe a 1970's concept, > but unfortunately there are no free nor open source implementation > of ISAM. > > This has been one of the killer problems in many open source > COBOL projects. > > MySQL used a version of ISAM, but recently they converted to > DB for the low level structures. > > So AFIK, DB is the only choice available. > > The closest implementation of VS*M on UN*X is C-IS*M, which by > the way is now owned by I*M. > > What I would to see is an OpenISAM project with the following criteria. > - XOpen ISAM standard conformity. > - Low level concurrence file locking. > > If there are any volunteers who would like to work on this project, > then the project is all your. > > David Essex MyISAM is still the standard filesystem used with MySQL. I use myisam extensively in my Cobol interface. It is fast and multi-user. I see only these difficulties with myisam: 1. The only documentation is what I wrote. It is not complete. 2. It does not support row-level locking. Instead, when rewriting, you provide a copy of the before buffer, and it checks the record has not been changed since then. 3. I found a couple of bugs in my usage. Either there are some bugs, or I was not using it properly - but see #1. 4. Monty Widenius is the only programmer who fully understands myisam. I am seeking a reliable, affordable Cobol. It is very encouraging to me that these three Cobol compiler teams are cooperating. Stephen, Sydney |