Excellent and Easy To Read

I have to disagree with the previous review. I will try to explain why I think 'b88zhou' review is inadequate after presenting my overview of this book.

After reading numerous pattern books, it is nice to see a pattern book with very good organization.

Each pattern is presented with the following subsections.

* Description
* Context
* Applicability
* Structure
* Iteractions
* Consequences
* Strategies
* Sample Code
* Related Patterns and Technology.

I specifically like 'Consequence' section because it outlines the 'bad' consequence of adopting the patter. This goes with the mantra of design patterns - there is no one good pattern. You trade off one design for another depending on the context of your domain.

Also each pattern is accompanied by UML class diagrams and UML sequence diagrams - this is a big plus in understanding pattern.

The sample code is written in Java/JDBC so you may need to understand Java but I believe this pattern is still relevant to ADO.NET and C++. [ ADO.Net does offer connected and disconnected database operation so some patterns may not be relevant - plus, event/delegate will aid in some patterns.]

Specific to what the previous reviewer say - here are my rebuttals.

>> Why do you want to make queries and database updates into factories? Looking at the sample code, does it really help decoupling?

The previous reviewer mentioned as 'factories' is the derivation of 'AbstractFactory'. If you do not understand why AbstractFactory aids in decoupling from the concrete implementation, I think you should re-read GoF book. The author uses AbstractFactory pattern extensively in context of "Input and Output Parameter" and "Cache Patterns". I do admit that sometimes "Input and Output Parameter patterns" may not need to use AbstractFactory but if you read 'Domain Assembler' pattern you will understand why. From Domain Assembler, you can see the benefit of having AbstractFactories for Selection, Domain Object, and Update -- assembling all these factories via interface not concrete implmentation - a basic idea of design to interface instead concrete implementation.

>> The "Cache Patterns" does not solve the problem of preventing stale entry or even attempt to describe how to invalidate cache entry, so no matter how efficient you get, the cache is not guaranteed to be up-to-date /correct.

Please re-read 'Cache Collector'. The pattern could have different name like 'Cache Garbage Collector'. He talks about how you can 'purge' old data. Also re-read 'Cache Replicator' for how to sync the cached data in distributed system.

>> I'm surprised "stored procedure" is not mentioned at all.

I guess you have not done too many DB oriented projects. The stored procedure is evil and add little value to OO programming. But if you want the stored procedure, just replace 'SELECT' or 'UPDATE' statements to whatever stored procedures you want to call. So I don't think you can add much with SP.

>> mature object/relational frameworks like EOF (Apple WebObjects) or TopLink

This book is not about Java Data Object or OR mapping. Object-Relational mapping tool is another beast.

I would recommend this book highly to anyone doing DB application development.

Other Reviews

• There is better one
• Useful patterns and interesting concepts
• Great book on persistence theory
• Good design pattern book in data access !!
• Excellent and Easy To Read