Problems using automap_base with DB2-s SAMPLE DB

[Krzysztof Malinowski]

Using the official docker form IBM for DB2 10.5.5:

https://hub.docker.com/r/ibmcom/db2express-c/

docker run -it -p 50000:50000 -e DB2INST1_PASSWORD=mypass -e LICENSE=accept ibmcom/db2express-c:latest bash

# create db
su - db2inst1
db2start
db2sampl

python requirements:

#!
sqlalchemy==1.0.17
ibm-db==2.0.5.1
ibm_db_sa==0.3.2

(btw. tried this with the newest versions also - same result)

OS:

#!
Ubuntu 14.04 64bit

Doing:

from sqlalchemy.ext.automap import automap_base
from sqlalchemy import create_engine

Base = automap_base()
engine = create_engine("db2://db2inst1:mypass@172.18.0.1:50000/SAMPLE")
Base.prepare(engine, reflect=True)

raises:

Traceback (most recent call last):
  File "db2_automap.py", line 8, in <module>
    Base.prepare(engine, reflect=True)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/ext/automap.py", line 777, in prepare
    generate_relationship)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/ext/automap.py", line 899, in _relationships_for_fks
    nullable = False not in set([fk.parent.nullable for fk in fks])
AttributeError: 'NoneType' object has no attribute 'nullable'

seems that some fk-s have incorrect parent and column attributes

[Mike Bayer]

the DB2 dialect is not produced or maintained by the SQLAlchemy project. Please see https://github.com/ibmdb/python-ibmdb

[Mike Bayer]

Duplicate of #3949.

[Krzysztof Malinowski]

OK. Thanks - I'll try my luck there :)

[Mike Bayer]

sorry, they have some issue in their reflection code and I need their help to sanity check on their end.

[Krzysztof Malinowski]

I've copied this issue over to https://github.com/ibmdb/python-ibmdbsa/issues/20

[Mike Bayer]

Raise if ForeignKeyConstraint created with different numbers of local and remote columns.

An :class:.ArgumentError is now raised if a :class:.ForeignKeyConstraint object is created with a mismatched number of "local" and "remote" columns, which otherwise causes the internal state of the constraint to be incorrect. Note that this also impacts the condition where a dialect's reflection process produces a mismatched set of columns for a foreign key constraint.

Downstream DB2 dialect has been reported as potentially causing this scenario.

Change-Id: Id51c34a6c43749bb582639f9c1dc28723482f0e5 Fixes: #3949 References: #3998

→ <<cset a78718b9340e>>

[Mike Bayer]

Raise if ForeignKeyConstraint created with different numbers of local and remote columns.

An :class:.ArgumentError is now raised if a :class:.ForeignKeyConstraint object is created with a mismatched number of "local" and "remote" columns, which otherwise causes the internal state of the constraint to be incorrect. Note that this also impacts the condition where a dialect's reflection process produces a mismatched set of columns for a foreign key constraint.

Downstream DB2 dialect has been reported as potentially causing this scenario.

Change-Id: Id51c34a6c43749bb582639f9c1dc28723482f0e5 Fixes: #3949 References: #3998 (cherry picked from commit a78718b9340e9840a470300932af178ce57c0f7d)

→ <<cset 0769b41cf291>>