> RDBMS are built for complex filtering - this is (part) of what SQL is > allabout - I wouldn't want to dismiss that - it would be a bad choice > all-around. >
A complex filter on a small set of items might be faster in Python than doing another database hit. And a simple filter might belong in the db if it has to go over lots of records. As I said, these are orthogonal considerations. > Conversely, simple-filtering is way too verbose using the DAL - it's an > overkill for that, and makes the code much less readable. > Don't know why you think that. > For simple filtering, well, I'd rather do it in python and get > readability, becuase the performance-benefits are negligible. > But I thought you were a fan of achieving negligible performance benefits at great cost (see below). > Now you've really lost me -- what does any of this have to do with RDBMS >> vs. NoSQL? And why shouldn't you do complex filtering in Python? >> > > See above. > Still don't know why you would want a NoSQL database or what it has to do with this topic. > db.Country(france).select().find(lambda r: r.Language != spanish and r. >> Population > 1000000) >> > > That's actully pretty nice - I didn't know I can do that - but what would > the "france" and "spanish" objects be in this case? Ids? > Well, you've sure made a lot of claims about what web2py needs without knowing much about what it already has. Those are ids. If they were rows, then you would just do france.id and spanish.id. > OK, please provide some benchmarks. What percentage decrease in CPU usage >> can we expect if we compare object identities rather than integer >> equivalencies? >> >> > > Really? You think I need to? > Yes, I think you need to. If this is only going to save a half a second of CPU time per day, I'm not going to build an ORM to get it. The question isn't how much faster the identity check is (and I don't think it's that much faster) -- the question is how much of your overall application CPU time is spent doing this kind of thing? Anthony -- --- You received this message because you are subscribed to the Google Groups "web2py-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
