SQLObject Overview

Contents

• SQLObject Overview
  • SQLObject Concept
  • Common Problems

SQLObject Concept

From the SQLObject web site:

SQLObject is a popular Object Relational Manager for providing an object interface to your database, with tables as classes, rows as instances, and columns as attributes.

SQLObject includes a Python-object-based query language that makes SQL more abstract, and provides substantial database independence for applications.

SQLObject provides three “groups” of interfaces. Based on how much SQL is “hidden” from the user.

Fully Hidden

This is the normal and preferred use of SQLObject. in this method instances are plain Python objects. It is the one is explained in the TGGuide and the SQLObject site

Semi Hidden

SQLObject provides sqlbuilder, which is a pythonic SQL-like query engine is the suggested for those complex queries that join multiple tables, or cases where more advanced SQL is need for example LIKE constrains or calling database built-in functions. The basic usage is also explained in our quick guide.

Fully Exposed

When you need to embrace the full power of SQL, you’ll need queryAll(). Remember this will bypass SQLObject and go directly to the DB2.0 api driver, so you will need to take care of writing SQL that works across all databases yourself, or make it very clear your app only works only on your chosen SQL engine. Check out a working sample.

Common Problems

How can I work with foreign keys?

A code example will probably make this clearer.

How do I select some fields from a table?

SQLObject is not a query wrapper. Try to get used to the object oriented way.

I really need to see what’s going on, show me the SQL!

Turn on debugging and see the SQL flow.

What other things do I need to account for?

See the list of SQLObject “gotcha’s”.

I don’t like the SQL queries SQLObject generates, they could be optimized doing <insert here>...

Then you will probably want to hop over to SQLAlchemy which lets you get dirty on the SQL.