29.04.2014 10:03, Dmitry Yemanov wrote: > 29.04.2014 02:02, Dimitry Sibiryakov wrote: > >> I may be wrong as often, but AFAIU this dream may be a reality if: >> >> 1) Eliminate DFW >> 2) Perform DDL (operations with system tables) in user transaction > > 3) Make garbage collector to handle system tables well > > And reimplement the undo log to handle page-level operations to rollback > physical DDL changes.
Not undo log, but garbage collector. It is its duty to clean up referenced objects (index nodes and BLOBs currently) for going record versions. > And reimplement the metadata cache to become two-level - global and > transaction-wise, with objects in the latter overriding objects in the > former. May be stop separate metadata cache at all and use ordinary data cache for reading system tables directly every time. It could help implement hot standby as well. > I'm pretty sure I've missing a dozen of other issues as well. I'm also sure that I missed a lot of things, such as record formats. But it is exactly the purpose of feature discussion - to point out to potential problems. -- WBR, SD. ------------------------------------------------------------------------------ "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
