I have been researching noSQL DB and have not been able to satisfactorily answer this for myself: Is it possible to construct complex queries against noSQL DB?
The type
In mongodb, you would just do something like db.mytbl.find({"vara": { $gt: 10}, "varb": 2, "varc": {$lt: 100 }})
db.mytbl.find({"vara": { $gt: 10}, "varb": 2, "varc": {$lt: 100 }})
See here, and here for examples