Products.SQLAlchemyDA 2.2 on PyPI

Zope ZSQL-SQLAlchemy Integration Wrapper

About SQLAlchemyDA

SQLAlchemyDA is a generic database adapter for Zope ZSQL methods, which are an older/legacy SQL templating feature for executing relational database queries from with in a Zope to transaction context.

SQLAlchemyDA provides an implementation in the form of a Zope "product" which wraps z3c.sqlalchemy, so that database connections are installable as objects in the Zope ZMI. Such connection objects can be set up to connect to any kind of database backend supported by SQLAlchemy using a database URI, such as Postgres, MySQL, Oracle, SQLite, MS-SQL, Firebird, Informix. However, some of these database backends have not been tested with the SQLAlchemyDA, so your mileage may vary.

In addition to ZSQL support, the SQLAlchemyDA makes it possible to use the standard SQLAlchemy API within a Zope context and participate in Zope transactions.

However, if you do not require ZSQL support, and only wish to call 'normal' SQLAlchemy APIs within Zope transactions, this package adds no value. Instead, you would be better off trying out zope.sqlalchemy, as recommended in the Zope book chapter on relational database connectivity.

Requirements:

Zope 4+
SQLAlchemy >= 0.5.0 (+ database specific low-level Python drivers)
z3c.sqlalchemy >= 1.5.0

Testing: testfixtures are needed to run tests.

Installation:

Download and install SQLAlchemy as egg or from the sources from PyPI (pip sqlalchemy). See

http://www.sqlalchemy.org

for details
Download and install z3c.sqlalchemy as egg or from the sources from PyPI (pip z3c.sqlalchemy). See

https://pypi.org/project/z3c.sqlalchemy/

for details.
Unpack the archive containing SQLAlchemyDA inside the "Products" directory of your Zope instance home.
After restarting Zope you go to the ZMI and create an instance of "SQLAlchemyDA" (as you would create some DA instance)
Click on the new created SQLAlchemyDA instance within the ZMI and configure your database connection through the "Properties" tab. The connection parameter 'dsn' must be specified as a valid SQLAlchemy DSN like

<dbschema>://<username>:<password>@<hostname>/<databasename>

Example:

postgres://admin:123@localhost:5432/TestDB
ZSQL methods should see the new DA through the selection widget of available database adapters
NOTE: you must have the low-level Python DB drivers installed in order to access a particular database. See

http://www.sqlalchemy.org/docs/dbengine.html#dbengine_supported

for details.

Configuration of SQLAlchemyDA:

'dsn' - SQLAlchemy compliant Database Set Name (see www.sqlalchemy.org/docs)
'transactional' - uncheck this property if you are working with a non-transactional

database like older versions of MySQL. Uncheck this property only if you see any commit() related error. Otherwise leave this property checked. Changing this property requires a Zope restart.
'quoting_style' - affects how strings are quoted in SQL. By default 'standard'

quotes strings correctly. Setting the value to 'no-quote' might solve quoting issues with some databases.

Using SQLAlchemyDA:

SQLAlchemyDA works as a database adapter as documented within "The Zope Book"

https://zope.readthedocs.io/en/latest/zopebook/RelationalDatabases.html

and can be used like any other DA together with ZSQL methods.

Tested with databases:

Postgres 7.4, 8.0-8.2
SQLite 3.3.X
Oracle 10g
MySQL is only supported for MySQL databases with transaction support. (see also z3c/sqlalchemy/README.txt)
MSSQL 2008

Known issues:

""" Database connection could not be opened ((ProgrammingError) (1064, You have an error in your SQL syntax near 'COMMIT . """

This bug might appear with older MySQL versions when opening/closing the connections manually through the ZMI. It should not affect the functionality of SQLAlchemyDA.