GBasedbt Alchemy Adapter

The GBasedbt Alchemy adapter provides the Python/SQLAlchemy interface to GBase 8s Servers. Fork from https://github.com/OpenInformix/InformixAlchemy

Version

x.x.x

Prerequisites

1. Python 3.5.x .
2. SQLAlchemy 0.7.3 or above.
3. DbtPy driver and DbtPyDbi

Install and Configuration

The GBasedbt Alchemy Python Egg component (.egg) can be installed using the standard setuptools provided by the Python Easy Install through Python Enterprise Application Kit community portal: http://peak.telecommunity.com/DevCenter/EasyInstall

Please follow the steps provided to Install "Easy Install" in the link above and follow up with these additional steps to install GBasedbt Alchemy:

1. To install GBasedbt Alchemy from source Standard Python setup should be used:: python setup.py build python setup.py install

Connecting

A TCP/IP connection can be specified as the following::

from sqlalchemy import create_engine

e = create_engine("gbasedbt://user:pass@host[:port]/database")

For a local socket connection, exclude the "host" and "port" portions::

from sqlalchemy import create_engine

e = create_engine("gbasedbt://user:pass@/database")

Known Limitations in DbtAlchemy adapter for GBase 8s databases

1. Non-standard SQL queries are not supported. e.g. "SELECT ? FROM TAB1"
2. For updations involving primary/foreign key references, the entries should be made in correct order. Integrity check is always on and thus the primary keys referenced by the foreign keys in the referencing tables should always exist in the parent table.
3. Unique key which contains nullable column not supported
4. UPDATE CASCADE for foreign keys not supported
5. DEFERRABLE INITIALLY deferred not supported
6. Subquery in ON clause of LEFT OUTER JOIN not supported