anchor.diff:  
   'fields' parameter is also used for controlling expansion of resource references. Symbol * at any level means - return all column fields, and only return resource references for synthetic fields. To expand those in full another '(*)' has to be appended, and that can be nested ad-infinitum.
   
  -There are two fields that currently can't be filterer out using this method - these are 'id', and 'self'.
  +There are two fields that currently can't be filtered out using this method - these are 'id', and 'self'.
   That may be addressed in the future.
   
   === Querying
  
positive.code: That would return messages starting with latest.
  
  
  Currently only targeted collection column fields can be specified for sorting. The following would work:
  
      ?sort=user.nick
  
  
negative.code: 
  That would return all messages from user 'MadHatter'. Note that 'user' field on 'message' is a synthetic field derived from a foreign key column 'user_id' that points to another table. Column 'nick' is in 'users' table, not in 'messages' table. A join select is performed in the background to execute this query.
  
  Another example using multiple conditions:
  
      curl -v -G 'http://localhost:8080/demo-app/sqldata/messages' --data-urlencode 'q={"user.nick": "MadHatter", create_time: {$gt: "2014-08-30"}}'
  
  That would further limit the results to those messages that are also fresher than the specified date.
  
  We can use $or, and $not, and make a more complex query:
  
  