I found problem when trying to move Liferay bundle on MySQL from Windows to Linux enviroment.
I have installed bundle on Windows MySQL and fill in some data (users, web content.....). After I finish customization I moved whole bundle to production Linux server, export DB and import it back to Linux MySQL.
Problem is that as default Linux MySQL is case sensitive and Windows MySQL case insensitive. Name of all tables on win are in lower case but Liferay on Linux expect all tables be in camel case. So Liferay detect he hasn't DB tables he needs and creates all tables again in camel case with sample data. It use then sample data to run whole web.
Liferay should has settings to force use all table names in lower case (if there is setting like this it should be pointed out in installing documentation for MySQL) or Liferay should detect if is not used tables in lower case.
I attached hot fix for anybody with same problem (it just renames all tables back to camel case).