Essential SQLAlchemy

✍ Scribed by Copeland, Rick

• Publisher: O'Reilly Media, Inc.
• Year: 2010;2008
• Tongue: English
• Category: Library

✦ Synopsis

Essential SQLAlchemy introduces a high-level open-source code library that makes it easier for Python programmers to access relational databases such as Oracle, DB2, MySQL, PostgreSQL, and SQLite. SQLAlchemy has become increasingly popular since its release, but it still lacks good offline documentation. This practical book fills the gap, and because a developer wrote it, you get an objective look at SQLAlchemy's tools rather than an advocate's description of all the "cool" features. SQLAlchemy includes both a database server-independent SQL expression language and an object-relational mapper).;Table of Contents; Preface; Audience; Assumptions This Book Makes; Contents of this Book; Conventions Used in This Book; Using Code Examples; How to Contact Us; Acknowledgments; Chapter 1. Introduction to SQLAlchemy; What Is SQLAlch; The Object/Relational "Impedance Mismatch"; SQLAlchemy Philosophy; SQLAlchemy Architecture; Engine; Connection Pooling; SQL dialect management; MetaData Management; Types System; SQL Expression Language; Object Relational Mapper (ORM); Chapter 2. Getting Started; Installing SQLAlchemy; Installing the SQLAlchemy Package; Installing setup tools.

✦ Table of Contents

Table of Contents
Preface
Audience
Assumptions This Book Makes
Contents of this Book
Conventions Used in This Book
Using Code Examples
How to Contact Us
Acknowledgments
Chapter 1. Introduction to SQLAlchemy
What Is SQLAlch
The Object/Relational "Impedance Mismatch"
SQLAlchemy Philosophy
SQLAlchemy Architecture
Engine
Connection Pooling
SQL dialect management
MetaData Management
Types System
SQL Expression Language
Object Relational Mapper (ORM)
Chapter 2. Getting Started
Installing SQLAlchemy
Installing the SQLAlchemy Package
Installing setup tools. Installing SQLAlchemy with easy_installTesting the install
Installing Some Database Drivers
Installing the SQLite driver on Python versions before 2.5
Other supported drivers
SQLAlchemy Tutorial
Connecting to the Database and Creating Some Tables
Performing Queries and Updates
Mapping Objects to Tables
Chapter 3. Engines and MetaData
Engines and Connectables
Configuring SQLAlchemy Logging
Database Connections and ResultProxys
Connection Pooling
MetaData
Getting Started with MetaData
Defining Tables
Table reflection
Column Definitions
Constraints
Primary keys
Foreign keys. UNIQUE constraintsCHECK constraints
Defaults
Active defaults
Passive defaults
Defining Indexes
The Index object
Creating Explicit Sequences
MetaData Operations
Binding MetaData
Create/drop MetaData and schema objects
Adapt Tables from one MetaData to another
Chapter 4. SQLAlchemy Type Engines
Type System Overview
Built-in Types
Generic Types
Dialect-Specific Types
Application-Specific Custom Types
Implementing a TypeDecorator
Creating a New TypeEngine
Chapter 5. Running Queries and Updates
Inserts, Updates, and Deletes
Insert Statements
Update Statements. Delete StatementsQueries
Basic Query Construction
The select?(??) function versus the select?(??) method
Result set objects
Operators and functions in WHERE clauses
Using custom bind parameters
Using literal text in queries
Ordering and grouping results, returning distinct values
Limiting results returned
Using the "generative" query interface
Joins and Set Operations
Joining selectables
Set operations (UNION, INTERSECT, EXCEPT)
Using aliases
Subqueries
Embedding subqueries in the column list
Correlated versus uncorrelated subqueries
Embedding subqueries in an IN clause. Embedding subqueries in the FROM clauseChapter 6. Building an Object Mapper
Introduction to ORMs
Design Concepts in the ORM
The data mapper pattern
The unit of work pattern
Declaring Object Mappers
Basic Object Mapping
Customizing Property Mapping
Using include_properties and exclude_properties
Customizing the name of the mapped column
Using synonyms
Mapping subqueries
Mapping composite values
Eager versus deferred loading
Mapping Arbitrary Selectables
Other mapper?(??) Parameters
Declaring Relationships Between Mappers
Basic Relationships
1:N relations
M:N relations.

✦ Subjects

Computer science;Python (Computer program language);SQL (Computer program language);Web databases;Electronic books