On Tue, 2005-01-18 at 12:45 -0800, Sailesh Krishnamurthy wrote: > >>>>> "Jonah" == Jonah H Harris <[EMAIL PROTECTED]> writes: > > Jonah> Replying to the list as a whole: > > Jonah> If this is such a bad idea, why do other database systems > Jonah> use it? As a businessperson myself, it doesn't seem > Jonah> logical to me that commercial database companies would > Jonah> spend money on implementing this feature if it wouldn't be > Jonah> used. Remember guys, I'm just trying to help. > > Systems like DB2 don't implement versioning schemes. As a result there > is no need to worry about maintaining visibility in > indexes. Index-only plans are thus viable as they require no change in > the physical structure of the index and no overhead on > update/delete/insert ops. > > I don't know about Oracle, which I gather is the only commercial > system to have something like MVCC. >
Perhaps firebird/interbase also? Someone mentioned that on these lists, I'm not sure if it's true or not. I almost think to not supply an MVCC system would break the "I" in ACID, would it not? I can't think of any other obvious way to isolate the transactions, but on the other hand, wouldn't DB2 want to be ACID compliant? Regards, Jeff Davis ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html