Jonathan Ellis wrote: > I don't understand the objection -- #3 is the only one that works in the > general case without inefficiency as in #1 or attaching extra metadata to > user tables as in #2. (SimpleORM uses #3 exclusively. :)
its a huge hit on the database to compare against all the columns youre updating, particularly if they are not indexed. suppose you were updating 200 rows of 18 VARCHAR(4000) columns, for example. or what if some of them are BLOBs, then youre totally out the window on that. seems very inefficient at best, a buggy headache at worst. so then we would say, well ok make this behavior as just an option. but then, the behavior is optional. so, better to use the version id option, which is very simple and easy to make efficient...the developer just adds a proper index to the version ID column. works with BLOBs etc no problem. however, option #3 may be implementable within MapperExtension, and if not, I am fine with looking into insuring that it has adequate hooks, for people who want stuff like #3 or whatever. I would like there to be a catalog of MapperExtension that provide all the patterns people want to use (like the polymorhic thing as well). basically, the philosophy addendum coming out of this and other issues that have already been raised is a "small and light core, a plugin system for all the heavy questionable stuff". I dont want anything chunky built in by default. ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ Sqlalchemy-users mailing list Sqlalchemy-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sqlalchemy-users
