From: Clifford Heath Date: 2007-03-22T19:25:09+09:00 Subject: Re: Object/Relational Mapping is the Vietnam of Computer Science Sam Smoot wrote: > On Mar 21, 6:00 pm, Clifford Heath wrote: >> SamSmootwrote: >>> * Knows the *data* is safe because the database is open-source, >> How does that help ensure *no* committed transaction is lost when >> someone trips over the power cord? > Eh? I'm not talking about ACIDity. I'm sorry, but the possibility of a power fail is an infinitely greater risk than that I won't be able to use my existing software and hardware to extract data from the proprietary (or not) storage format that software might use. You're the one that said "the data is safe". I beg to differ. > I'm talking about the horse people > love to beat about loosing your data due to vendor lock-in Ok. Perhaps you can explain just how vendor lockin would cause me to loose (sic) data? I still have the files, and the software, and the hardware, and backups or redundancy for all. Where's the chance of loss that's mitigated by having the source code as well? > On the subject of ACIDity though, here's a developer press-release on > an older version, along with benchmarks and tests for crash > simulations: http://developer.db4o.com/blogs/product_news/archive/2006/06/02/25420.aspx > > Now, could be that you just don't trust them. No, I trust them. I don't, however, trust them as much as tests that I know have been conducted, using thread-scheduling hooks to explore very many of the infinite combinatoric paths of such things, and in the process, do the same "stop the world" recovery tests. Such exploration takes years, thousands of clients, and trillions of transactions, before real trust is deserved. But in any case, it's not my data that's at risk, and it's not me who needs to be convinced. It's my dozens of customers who are backing up tens of gigabytes of transaction log every day, from machines costing hundred of $K, and who are using software that's doing the same for tens of thousands of other customers for years, without the vendor being sued our of existence - as happened to inferior players during the 80's - who need to be convinced. For better or for worse, and even though they now seem to have risen above their ignorance, the authors of MySQL, who apparently didn't know what a transaction is, have unfortunately tarred most of the open source database world with the same brush. Unfair, but life is. Clifford Heath.