title: Is there any nosql flat file database just as sqlite?
body: <p>Short Question:
  Is there any nosql flat-file database available as sqlite?</p>
  
  <p>Explanation:
  Flat file database can be opened in different processes to read, and keep one process to write. I think its perfect for read cache if there's no strict consistent needed. Say 1-2 secs write to the file or even memory block and the readers get updated data after that.</p>
  
  <p>So I almost choose to use sqlite, as my python server read cache. But there's still one problem. I don't like to rewrite sqls again in another place and construct another copy of my data tables in sqlite just as the same as I did in PostgreSql which used as back-end database.</p>
  
  <p>so is there any other choice?thanks!</p>