When you need 17 tables for categories and 67 tables (yes, freaking 67 tables) to manage products in a shopping cart, as a developer you know you have messed up something a big time. That is exactly what Magento has done. What's more? Magento tom-toms about this very "feature" and shows how flexible structure they have got. However, everybody and his aunt knows how flexible or rather inflexible Magento is.
Slow Slow Slow!!!
The fact that Magento has such an insane database structure it's not and is never going to be fast. It is dead slow in comparison to other carts. Their database structure would kill any database engine. - and they know it. That's why they use the ad-hoc solution of cache management. But it never occurred to them that in a heavy traffic site the cache may do the role of evil. Even cache management took them only thus far. It still is slow. It will require special server settings to make Magento run reasonably well.
Customizable?
Magento claim that their's is a highly customizable structure. That must be a jock of the century!! A flexible system would mean that even a less skilled programmer will also be able to understand and customize a program. But that is not the case with Magento. You will need highly skilled programmers not only just to customize it but even to maintain it. A skilled programmer would tweak any system (good or bad) to suit his needs. But in Magento he will take lot more time to do it than a normal system.
For big organization?
It is a popular belief on internet that Magento is for larger organization. How exactly is that? Why exactly an organization needs a crazily overbuilt and hard to maintain system? Just because Magento is doing an easy stuff in ridiculously hard way, it doesn't make it better for a big org. I would think that if you are creating a website for a big org, you will rather create it from scratch to suit all its needs. The open source platforms provide generalized solution and lot of its features you will not want. Neither you will want the same admin panel. But as an organization you will still need lot of customization which will require hacks/patches in the opensource's default code. So if the budget is not a problem, it is always good to go for the customized solution.
For small shops?
A big NO. A Small shops will want a simple solution which is easy to program and maintain. Magento offers none of these. A Magento implementation will cost you much more money than any other simpler opensource. This is because Magento requires special developers and special hosting. And this is just an up-front cost. As you go along the cost of maintaining a Magento implementation will be bigger.
Magento version migration?
Well all I would say is that - Do it at your own risk!!!
EAV Model?
For me EAV = TWKTDEC
TWKTDEC = The Winner of "Kill The Database Engine" Competetion.
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In short Magento is the "Anti Gravity Pen" that nobody really needed and its structure is "Burg Dubai" which is crazily overbuilt and which almost brought down the great empire.
For me EAV = TWKTDEC
TWKTDEC = The Winner of "Kill The Database Engine" Competetion.
---------------------------------------------------------------------------------------------
In short Magento is the "Anti Gravity Pen" that nobody really needed and its structure is "Burg Dubai" which is crazily overbuilt and which almost brought down the great empire.