modify DB records in prestashop 1.5.6

[alreadynight]

I have a strange situation:

when I change a value directly in the prestashop DB (ie: date_add in the table ps_product), in the frontend nothing happens.

If I update a product via backoffice (not necessary the same product updated directly in the DB), my modify appears.
During update via backoffice I don't change anything, simply I enter and I click on "save" button.

I tried to clean my cache without success.

It seems there is a kind of "DB cache".

Any suggestions?

Thanks

Edited October 15, 2013 by alreadynight (see edit history)

[Perrotekel]

I have same problem..

 

 

Any solution?