I am trying to develop a schema for document store (using db_set_schema). What exactly are the data types acceptable to use with the schema?

What I would like to have is one of the fields be an array of JSON objects with a specific format. An example of what I would like is below. Is this possible.

%
$schema = {
    _id: 'integer',
    name: 'string',
    data: [
        {
            value: 'integer',
            units: 'string'
        }
    ]
}
%

:: @c1moore added on 11 Nov ’15 · 18:55

The most important question is what are the acceptable data types.