Hi Yiiers,
i just have a proposal to develop a "little" ERP system with Yii, but i want to know if there is any disadvantages to use Yii as a core in such complexe system.
is there a problem that can be in :
memory using
time execution
preformance with big data in the database.
etc.
I think it is save to say that one can’t answer this question without real facts about what you are planning to do. Yii is very efficient and fast so I doubt that your system will have any problems that are caused by Yii itself. The only thing that I would suggest when it comes to big data: ActiveRecord wasn’t made for reading and updating 1000’s of models at a time. It is fine for 90% of all use cases but it tends to be memory consuming and slower compared to simple DAO/PDO statements which is quite logical as AR is build on top of that. So my 2 cents: First go with ActiveRecord as it is easy to implement and already well tested and if you experience some performance bottlenecks add caching or revise your code and go with DAO. So to sum that up: Your bottleneck will (as always) be the database, not the framework itself
Thanx ! 
no problem with Yii, please check my ERP System, called Capella ERP System at
http://www.capellaerp.com (user: romy, pass: demo)
or
http://erp.mozy.co.id (user: yayan, pass: demo)
the two application, based on Capella ERP System for Network Provider Consultant Company
Wow!! I had a look at your system and have to admit that I was impressed!! 
I hope I may be able to attain such a level in the future. Don’t you have some advice/tips for a newbie like me?
Nice info about ERP system
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