Introduction to SQLAlchemy
SQLAlchemy is the premier SQL toolkit for Python. SQLAlchemy exposes the full power of SQL while remaining easy to use for the basics, and is flexible enough to work with existing database schemas as well as fresh designs. SQLAlchemy is used in production by leading Python web frameworks Pylons and Turbogears as well as many other web and non-web developers.
This tutorial teaches SQLAlchemy's object-relational mapping to automate painlessly loading and persisting objects from and to your database, even when complex relationships exist.
Presenter
Jonathan Ellis is co-author of the FormAlchemy library and the author of the SqlSoup extension to SQLAlchemy.
Requirements
Python experience: intermediate. You should already have some hands-on experience with Python and be comfortable reading modern Python code.
SQL experience: beginning. You should know how to SELECT, INSERT, and DELETE, and how to read queries involving JOINs, but we will only be reading the SQL generated by SA, not writing our own.
ORM experience: prior experience with an object-relational mapper is not necessary.
Class Outline
Introduction
- Philosophy
- SA features
Fundamentals
- Introduction to ORM
- Data Mapper pattern vs Active Record
- Tables
- Mapping basics
Queries
- Conditions, operators
- Joins
- lazy / eager loading
- Relation-based queries
Sessions & identity map
- detatching, attaching objects
- Lifecycle relations
More Mapping
- one to one, many to many
- backreferences
Extensions
- SqlSoup
.