Schema Design when migrating data from relational into document

[Mohammad Prabowo]

Hi, suppose i have relational db with schema like this

employees-schema<http://dev.mysql.com/doc/employee/en/images/employees-schema.png>

I want to try converting it into document. I have two question:

   1. The main strength of Document is that it is 'self contained'. Meaning
   we don't need to do JOIN stuff, and all data that is needed are contained
   within documents. So, should i choose to use nested documents like this :

   {
       "emp_no": "...",
       "birth_date": "...",
       "first_name": "..",
       "last_name": "..",
       "gender": "..",
       "hire_date": "..",
       "titles": {
           "title": "...",
           "from_date": "...",
           "to_date": "..."
       },
       "salaries": {
           "salary": "...",
           "from_date": "...",
           "to_date": "..."
       }
   }


   or using different documents like this :

   [
       {
           "doc_name": "employees",
           "emp_no": "...",
           "birth_date": "...",
           "first_name": "..",
           "last_name": "..",
           "gender": "..",
           "hire_date": ".."
       },
       {
           "doc_name": "titles",
           "from_date": "...",
           "to_date": "..."
       },
       {
           "doc_name": "salaries",
           "salary": "...",
           "from_date": "...",
           "to_date": "..."
       }
   ]


   2. I want to benchmark MySQL and CouchDB with
YCSB<https://github.com/brianfrankcooper/YCSB/wiki>.
   Is there are db layer that has been built for CouchDB ?

Thanks in advance