Re: [Sqlalchemy-tickets] [sqlalchemy] #2813: Buglette with annotated join condition

[sqlalchemy <mi...@zz...>]

#2813: Buglette with annotated join condition
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      Reporter:  dairiki          |      Owner:  zzzeek
          Type:  defect           |     Status:  new
      Priority:  lowest           |  Milestone:  0.8.xx
     Component:  orm              |   Severity:  no triage selected yet
    Resolution:                   |   Keywords:
Progress State:  awaiting triage  |
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Comment (by zzzeek):

 yeah not sure how to handle this, annotation() makes a copy of the Column,
 and in this case it's copying it before it gets a table assigned.

 If you use this patch:

 {{{
 #!diff
 diff --git a/lib/sqlalchemy/orm/relationships.py
 b/lib/sqlalchemy/orm/relationships.py
 index f37bb8a..7d8a97d 100644
 --- a/lib/sqlalchemy/orm/relationships.py
 +++ b/lib/sqlalchemy/orm/relationships.py
 @@ -1866,6 +1866,8 @@ class JoinCondition(object):
      def _has_annotation(self, clause, annotation):
          for col in visitors.iterate(clause, {}):
              if annotation in col._annotations:
 +                if col.table is None:
 +                    raise sa_exc.ArgumentError("column %s doesn't have a
 Table" % col)
                  return True
          else:
 }}}

 it raises an error, but this isn't great.

 the workaround is to use a string, `primaryjoin="(remote(TableOne.x) ==
 foreign(TableTwo.x))"`.

 i might have realized this issue a while back but i dont have a good idea
 how to deal with it.

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Ticket URL: <http://www.sqlalchemy.org/trac/ticket/2813#comment:1>
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