title: Modifying all dates/timestamps in a database vs static server date
body: <p>I'm working on an web application that needs a demo/example version, so that potential customers can see it in action. It uses some queries to create overviews like "list of invoices send in the last week". In order to create a demo version with good examples, it would be best that these overviews are always the same.</p>
  
  <p>The underlying database will probably be restored every night, using some backup. However, to make sure that the "list of invoices send in the last week" page always contains some results, the dates will need to be modified.</p>
  
  <p>What would be the best way to achieve this? The application needs approx 50 tables (MySQL), all with an average of about 2 date/datetime fields. Creating a query that increases all this fields with 1 day would be a tedious job (and would need to be adjusted if more tables are added).</p>
  
  <p>So I thought of the following: just use a static date on the demo website/server. This could be done by decreasing the server date by 1 every night, and this would ensure that the queries always retrieve the same results. Is this be a good solution for this problem, or would it introduce other problems?</p>