Appendix A. SQLAlchemy

• A.1 A Quick Tour of SQLAlchemy 432

• A.2 SQLAlchemy in TurboGears 434

• A.3 Data Mapper and Active Record 435

• A.4 More about ActiveMapper 436

• A.5 How Objects Are Cached in SQLAlchemy 437

• A.6 Should I Use SQLAlchemy or SQLObject? 438

• A.7 Migrating a Project to SQLAlchemy 439

• A.8 Deployment Configuration 439

• A.9 Application Configuration 439

• A.10 Class Definitions 440

• A.11 Changing Calls to byName Methods 447

• A.12 Updating Queries 447

• A.13 Final Thoughts 448

SQLAlchemy is a powerful database-independent SQL layer and object-relational mapper library. It is newer than SQLObject and doesn't have as many tools within TurboGears, but TurboGears supports SQLAlchemy to handle those cases where SQLObject is not enough. This appendix includes a guide for migrating your SQLObject application to SQLAlchemy.