On 5/1/2014 11:45 PM, Dmitry Yemanov wrote: > 2- In an version based database like Firebird each row will need to be read > to confirm the current value of the target field. > It's not about version based databases, it's just about our index > implementation. And there are possibilities to avoid record lookups even > in our implementation. >
OK, the alternative to record lookups is to store the transaction id in index. This would require an index insertion for all indexes defined on a table even if the key value didn't change. It would also require a corresponding index deletion for each index defined on the table when a record version was garbage collected. The update performance would go straight down the toilet. And this doesn't include the performance drop due to fluffed up indexes. If you have a third alternative, by all means share it. ------------------------------------------------------------------------------ "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE Instantly run your Selenium tests across 300+ browser/OS combos. Get unparalleled scalability from the best Selenium testing platform available. Simple to use. Nothing to install. Get started now for free." http://p.sf.net/sfu/SauceLabs Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
