On Fri, Mar 2, 2018 at 11:30 AM, Harshvardhan Gupta <harshsay...@gmail.com> wrote: > There is no way to achieve what I want without doing the query? > merge seems to do the whole query.
you have a User row, and you want to load columns in that row, like "full_name". How would you like to achieve that without emitting a query? > I also have asked this question on stack overflow which talks about my use > case : > > https://stackoverflow.com/questions/49062520/querying-properties-of-transient-models-in-sqlalchemy > > > On Friday, 2 March 2018 11:27:31 UTC-5, Mike Bayer wrote: >> >> On Fri, Mar 2, 2018 at 11:21 AM, Harshvardhan Gupta >> <harsh...@gmail.com> wrote: >> > I also tried loading a related attribute , and it still returns None. >> >> >> you need to merge the object: >> >> my_user = session.merge(my_user) >> >> that is your only option. E.g. do the query. >> >> > >> > >> > On Friday, 2 March 2018 11:00:47 UTC-5, Harshvardhan Gupta wrote: >> >> >> >> Thanks, I am able to call my object, but the attribute prints none: >> >> >> >> >> >> E.g. my model is: >> >> >> >> class User(Dictifiable, db.Model, UserMixin): >> >> __tablename__ = 'user' >> >> >> >> id = Column(Integer, Sequence('user_id_seq'), primary_key=True) >> >> full_name = Column(String(50)) >> >> >> >> >> >> And this is what I have done : >> >> >> >> `u_lazy = User(id=1)` >> >> `db.session().enable_relationship_loading(u_lazy)` >> >> when i try to print u_lazy.full_name, it shows null (it is non null in >> >> db >> >> ) >> >> >> >> >> >> On Friday, 2 March 2018 10:55:11 UTC-5, Mike Bayer wrote: >> >>> >> >>> On Fri, Mar 2, 2018 at 10:52 AM, Harshvardhan Gupta >> >>> <harsh...@gmail.com> wrote: >> >>> > Thanks for the reply. >> >>> > >> >>> > There is a guarantee that the user will exist ,why is why I want to >> >>> > prevent that extra db query. >> >>> > >> >>> > When I try to do enable relationship loading ,I get the error : >> >>> > Scoped session has no attribute enable relationship loading. >> >>> >> >>> that's a scoped_session(), not a Session, access the Session by >> >>> calling it: scoped_session().enable_relationship_loading(obj) >> >>> >> >>> > >> >>> > -- >> >>> > 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+...@googlegroups.com. >> >>> > To post to this group, send email to sqlal...@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+...@googlegroups.com. >> > To post to this group, send email to sqlal...@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. -- 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.
