Can you show the part of *your* code that is triggering the error, and explain what you are trying to do? Plain python properties aren't normally very useful when accessed via a class. "Genome.attributes" returns a property object, not the return value from the function, and I don't understand what you are trying to do with it.
Thanks, Simon On Mon, Jan 24, 2022 at 2:03 AM Simon <htlbyd...@gmail.com> wrote: > > Hi there, > > I got a problem about 'sqlalchemy.exc.ArgumentError: SQL expression object > expected, got object of type <class 'property'> instead' > > My SQLAlchemy version is 1.3.22. I have a database like > > Class Genome: > id = Column(Integer, primary_key=True) > created_date = Column(Datetime, nullable=False) > > @property > def attributes(self): > return "something" > > > If using the query, it reports an error through the elements.py in the > sqlAlchemy > > def _literal_as(element, text_fallback): > if isinstance(element, Visitable): > return element > elif hasattr(element, "__clause_element__"): > return element.__clause_element__() > elif isinstance(element, util.string_types): > return text_fallback(element) > elif isinstance(element, (util.NoneType, bool)): > return _const_expr(element) > else: > raise exc.ArgumentError( > "SQL expression object expected, got object of type %r " > "instead" % type(element) > ) > > This exception is not raised if I directly query genome's column name such as > created_date or id. > > I am wondering 1) could the column name and property be used interchangeably > in some way? Or say how could to query a table's property in the way of > querying a table's column? 2) what are some significant differences between > table's column name and property? > > Thanks. > > > > > -- > 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 view this discussion on the web visit > https://groups.google.com/d/msgid/sqlalchemy/7f03c9bb-9324-4e3e-8aea-cd0d46f9021bn%40googlegroups.com. -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/CAFHwexfKm%2Bx8AMg8de%2BXx5CQ6AM62%2BWfth3v%2BgGB8LzE9SbK%3Dw%40mail.gmail.com.
