The chaining-friendly method you are looking for is probably with_entities():
http://docs.sqlalchemy.org/en/latest/orm/query.html#sqlalchemy.orm.query.Query.with_entities Simon On Fri, Feb 9, 2018 at 11:52 AM, Jeremy Flowers <jeremy.g.flow...@gmail.com> wrote: > From watching your videos I always thought some sort of query object would > be returned from the query() operation, so method chaining (aka fluent > interface) could always be performed.. in a way that is analogous to JQuery. > But what I'm doing seems to be breaking that paradigm. What am I doing wrong > or not getting? > > On Thursday, 8 February 2018 20:29:45 UTC, Jeremy Flowers wrote: >> >> I've seen you can do things like this: >> fields = ['jobmst_type', 'jobmst_name'] >> print(session.query(Jobmst).options(load_only(*fields)).first()) >> >> But according to the documentation, you should be able to do something >> with Query values() too. >> But once again I seem to be dumbfounded by the syntatic sugar. >> >> What data type does the list of values need? >> Is there a way to introspect that ahead of time? >> >> Thought I was onto something with .base_columns, but that didn't work >> either... >> >> I ended up with something like an instrumentalAttributes mismatch. >> print(session.query(Jobmst) >> .values([Jobmst.jobmst_type.base_columns, >> Jobmst.jobmst_name.base_columns >> ]) >> .first() >> ) >> >> sqlalchemy.exc.InvalidRequestError: SQL expression, column, or mapped >> entity expected - got '[{Column('jobmst_type', Numeric(scale=0, >> asdecimal=False), table=<jobmst>, nullable=False)}, {Column('jobmst_name', >> String(length=256), table=<jobmst>, nullable=False)}]' >> >> BTW: I'm aware of querying with things like query(Jobmst.jobmst_type, >> Jobmst.jobmst_name) too - but looking to understand what values expects. >> Mike, Can documentation not specify type? > > -- > SQLAlchemy - > The Python SQL Toolkit and Object Relational Mapper > > http://www.sqlalchemy.org/ > > To post example code, please provide an MCVE: Minimal, Complete, and > Verifiable Example. See http://stackoverflow.com/help/mcve for a full > description. > --- > 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 https://groups.google.com/group/sqlalchemy. > For more options, visit https://groups.google.com/d/optout. -- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- 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 https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
