title: What database do i choose if I need to make an inventory system
body: <p>I need to develop an inventory system(Windows application). 
  This INV System will be installed on the HQ(always online) and on different sites(locations) which works off line and goes online only once to transfer the data to the server on HQ.</p>
  
  <p>Which database(free)(huge data) can be used is my first question. 
  Secondly, how to update daily changes made on local database to database on server.</p>