On Sep 11, 2013, at 10:36 PM, Joe Martin <jandos...@gmail.com> wrote:
> Thank you for your reply. Then I thought the following would work:
>
> company_schema = 'c' + str(company_id)
> db.session.execute(CreateSchema(company_schema))
> db.session.commit()
> meta = db.MetaData(bind=db.engine)
> for table in db.metadata.tables.items():
> if table[1].name == 'customer':
> table[1].tometadata(meta, company_schema)
> elif table[1].name == 'company':
> table[1].tometadata(meta, 'app') # or
> table[1].tometadata(meta)?
> print meta.tables.items()
> meta.create_all()
>
> Now I see print meta shows 2 tables, but somehow error is still the same:
> "NoReferencedTableError: Foreign key associated with column
> 'customer.company_id'
> could not find table 'company' with which to generate a foreign key to
> target column 'id' "
>
> However, with my original metadata I was able to create both tables:
> app.company and public.customer.
> So, I'm confused with the issue. Thanks for your time.
The way it works is this:
a Table object that has a ForeignKey() object inside of it, is going to want to
find the target column that this ForeignKey points to.
There are two ways to specify it. One is via string:
ForeignKey("<schemaname>.tablename.columname")
if you use that approach, the MetaData for this table *must have a Table with
exactly that target name present*. The table[1].name == 'company' conditional
you have seems to be doing this, but then the error you're showing me doesn't
include "app" inside of it, so perhaps you want to do tometadata(meta, None),
not sure.
the other way, which might make this all easier, is to put the actual Column
object in the ForeignKey:
ForeignKey(my_company_table.c.id)
if you do it that way, then you can go back to your original approach where you
don't copy "company" at all - if ForeignKey is given the Column directly, then
no string lookup in the MetaData is needed and you can point to any Table
anywhere.
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