Check out example codes for "lopping rows rethinkdb". It will help you in understanding the concepts better.

Code Example 1

r.table('users').filter(r.row('age').gt(5)).run(conn, callback)

Code Example 2

r.table('users').filter(function(doc) {
    return doc('name').eq(r.table('prizes').get('winner'))
}).run(conn, callback)

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