On Monday, October 7, 2013 8:11:42 AM UTC-4, Michele Comitini wrote: > Joahnn, yes on large datasets the ordering is devastating, since it causes > full table sweep even if not needed. > > We must add the orderby_on_limitby paramenters in the book because it > impacts large datasets. > Shortcut queries that return single values like db.table(id=3) are already > optimized to avoid ordering. >
db.table(id=3) is for returning the sole matching record, so you don't have to worry about the database's arbitrary ordering of results. But when using limitby to return a particular subset of records (e.g., when doing pagination), don't you need to specify an orderby to guarantee that the results on each query will remain in the same order? Anthony -- Resources: - http://web2py.com - http://web2py.com/book (Documentation) - http://github.com/web2py/web2py (Source code) - https://code.google.com/p/web2py/issues/list (Report Issues) --- 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.
