On Sunday, October 20, 2013 3:17:43 PM UTC-4, Niphlod wrote: > calc_field = db.hourlydata.TotalAsh / db.hourlydata.TotalMass > rows = db( db.hourlydata.DevId==1 ).select( db.hourlydata.DevId,calc_field > ) > for row in rows: > print row.DevId, row[calc_field] > > > tl;dr: every expression gets saved into the row as a field in the _extra > dict (see for yourself printing "row"). > That field is retrievable passing the string representation of the > expression itself as a key. The smart thing here is that you can easily > assign that calculated field to a variable and use that variable as a key > later for accessing the value directly from the row (and save lots of > typing ^__^) >
Also, because the key is the query language code that is generated for the expression, technically it can vary from adapter to adapter -- so it's better to store it in a variable and use the variable rather than hard-coding the key, which may change with a different adapter. 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.
