I don't know which database you are using, but in postgresql there certainly is a function called "length" (see http://www.postgresql.org/docs/9.1/static/functions-string.html)
On Thu, Dec 10, 2015 at 2:04 PM, SF Markus Elfring < elfr...@users.sourceforge.net> wrote: > > As stated in the docs: > > "Note that any name not known to func generates the function name as is > > - there is no restriction on what SQL functions can be called, > > known or unknown to SQLAlchemy, built-in or user defined." > > I get an error message like "Function len(text) does not exist." if I try > something out like the following on a string field. > > … > for length, \ > incidence in session.query(func.len(position.label), > func.count(position.label) > ).group_by(func.len(position.label)) \ > .order_by(func.len(position.label)): > … > > > Is it interesting that the following approach seems to work instead? > > … > for length, \ > incidence in session.query(func.length(position.label), > func.count(position.label) > > ).group_by(func.length(position.label)) \ > > .order_by(func.length(position.label)): > … > > > How is the function "length" mapped to the SQL function "LEN"? > > Regards, > Markus > > -- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sqlalchemy+unsubscr...@googlegroups.com. > To post to this group, send email to sqlalchemy@googlegroups.com. > Visit this group at http://groups.google.com/group/sqlalchemy. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
