title: Magento 2 bug when saving configurable products
body: <p>I'm having a weird issue with Magento 2 and configurable products.</p>
  
  <p>I am absolutely not able to create configurable products on my local server. When I try to save a configurable product, I get a SQL warning and it becomes a simple one.
  I was about to give up, but same operation worked when I installed Magento 2 on my web hosting provider.</p>
  
  <p>Everything is ok since I created a new user with admin capabilities.
  With my account, there is no problem with configurable products, but with his account it's the same as previously described on my local server:
  - he cannot create configurable products (sql error + the product becomes simple)
  - when he edits and save configurable products that I have previously created, the products lose their name, custom attributes, become inactive and not visible individually.</p>
  
  <p>I have searched for a long while on forums but couldn't find answers to this problem.
  Did anyone get the same bug with configurable products and Magento 2?
  Thanks in advance!</p>