On Wed, Sep 13, 2017 at 12:01 PM, Kent <jkentbo...@gmail.com> wrote:
> I've got a strange relationship on a legacy Oracle 8i database which I need
> to support (whether I like it or not).
dude! it is 2017. get on this client! :) I literally have to
maintain this feature for you personally :).
>
> The cleanest approach is specifying that the 'primaryjoin' to the
> relationship in the mapper should include an extra join clause. I hate
> doing this, but after many other approaches, I've found this is by far the
> cleanest approach due to bad database design (which I can't control --
> legacy).
>
> Anyway, the attached script shows an simplified, analogous mock-up, which
> works correctly when joins are ANSI and incorrectly with use_ansi=False.
>
> The script demonstrates an inconsistency in use_ansi True vs. False on
> sqlalchemy version 1.1.14 (although my sqlalchemy is older).
>
> In the use_ansi=False SQL, the correct "fix" would be changing the rendered:
>
> AND bugs_1.deathdate IS NULL
>
> into
>
> AND bugs_1.deathdate(+) IS NULL
>
> This then matches the ANSI join and works on 8i (I've tested it).
>
> Is this something we can fix? Since the column is on the remote table and
> specified in the join condition, it really needs "(+)" after the column name
> in SQL. This accomplishes the same thing as the ANSI version placing this
> join condition in the "ON ..." clause instead of the "WHERE".
>
> Alternatively, is there a hack I could use to fix the rendered SQL on
> joinedloads for this particular relationship?
the miracle of Docker means that I now have easy to run Oracle, SQL
Server, etc. databases anywhere I need them so I can quickly confirm
that this works with ansi or not:
mapper(Rock, rocks_table,
properties={
'livingbugs': relationship(Bug,
primaryjoin=and_(
bugs_table.c.rockid == rocks_table.c.id,
bugs_table.c.deathdate.op("(+)=")(null()),
)),
})
>
> Thanks very much in advance!
> Kent
>
> --
> 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.
