this issue is fixed, you can download the tip of 0.6 or 0.7 in the "development versions" section at:
http://www.sqlalchemy.org/download.html On May 19, 2011, at 11:49 AM, Michael Bayer wrote: > this is a bug ticket http://www.sqlalchemy.org/trac/ticket/2169, ill have a > fix committed in a few minutes. > > On May 19, 2011, at 5:20 AM, boothead wrote: > >> Hi, >> >> I have a declarative class that I'd like to be able to add an >> attribute to: (please ignore the eye burning capitals - it's an >> existing schema :-) ) >> >> class Schedule(Base): >> __tablename__ = "SomeSchedule" >> __table_args__ = ( >> dict(schema="Schedule", useexisting=True) >> ) >> >> def __str__(self): >> return "%s %s to %s" % (self.Name, self.Start, self.End) >> >> query = Session.query_property() >> >> id = Column(Integer, primary_key=True) >> NameId = Column(Integer, ForeignKey("reference.name.id"), >> nullable=False) >> Value = Column(Integer, nullable=False) >> Start = Column(Date, nullable=False) >> End = Column(Date, nullable=False) >> >> On instances of this class I would like an attribute NextValue which >> would be the Value column of the row in the table where self.id == >> next.id and self.End == next.Start >> >> So do I use a column_property like: >> >> rs1 = Schedule.__table__.alias('rs1') >> rs2 = Schedule.__table__.alias('rs2') >> >> next_val_select = select([rs2.c.Value], from_obj=[rs1.join(rs2, >> rs1.c.NameId==rs2.c.NameId)])\ >> .where(rs1.c.End==rs2.c.Start) >> >> RollSchedule.NextContract = column_property(next_contract_select) >> >> This gets me almost there, but the from clause in the main select is >> aliased to rs2 which means that the columns are messed up: >> >> SELECT [RollSchedule_1].id AS [Schedule_RollSchedule_id], >> [RollSchedule_1].[NameId] AS [Schedule_RollSchedule_NameId], >> [RollSchedule_1].[Contract] AS [Schedule_RollSchedule_Contract], >> [RollSchedule_1].[Start] AS [Schedule_RollSchedule_Start], >> [RollSchedule_1].[End] AS [Schedule_RollSchedule_End], (SELECT name_1. >> [stringId] >> FROM reference.name AS name_1 >> WHERE name_1.id = [RollSchedule_1].[NameId]) AS anon_1, (SELECT rs2. >> [Contract] >> FROM [Schedule].[RollSchedule] AS rs1 JOIN [Schedule].[RollSchedule] >> AS rs2 ON rs1.[NameId] = rs2.[NameId] >> WHERE rs1.[End] = rs2.[Start]) AS anon_2 >> FROM [Schedule].[RollSchedule] AS rs2 >> >> >> Or should I do it more like this: >> >> RollSchedule.NextRolls = relationship(Schedule, >> >> primaryjoin=(Schedule.NameId==Schedule.NameId) & >> (Schedule.End==Schedule.Start), >> foreign_keys=[Schedule.NameId], >> # lazy="joined", >> join_depth=2) >> >> and have an assocaition_proxy. >> >> The query I'm looking for is: >> >> SELECT rs."NameId", rs."Contract", rs."Start", rs."End", >> ( >> SELECT reference.name."stringId" >> FROM reference.name >> WHERE reference.name.id = rs."NameId") AS anon_1, >> ( >> SELECT rs1."Contract" >> FROM "Schedule"."RollSchedule" rs1 >> JOIN "Schedule"."RollSchedule" rs2 >> ON rs1.nameId = rs2.nameId >> WHERE rs2."End" = rs1."Start" and rs.id = rs2.id >> ) AS anon_2 >> FROM "Schedule"."RollSchedule" rs >> >> >> Thanks in advance >> Ben >> >> -- >> You received this message because you are subscribed to the Google Groups >> "sqlalchemy" group. >> To post to this group, send email to sqlalchemy@googlegroups.com. >> To unsubscribe from this group, send email to >> sqlalchemy+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/sqlalchemy?hl=en. >> > > -- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To post to this group, send email to sqlalchemy@googlegroups.com. > To unsubscribe from this group, send email to > sqlalchemy+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/sqlalchemy?hl=en. > -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.
