JSon attributes

In GoDo ,complex tuple attributes are serialized in json format . The advantages are obvious

You can easily read the content of the of the attribute : this facilitates debugging.
You necessarily do not use BLOBs : every database handles BLOBs and CLObs in different ways and some times they are very trick. JSon attributes are mapped as String attributes .
They are type safe : the json API serializes and deserializes using json strings. When some object is constructed using this strings , the API infer the correct type so the application don't bother converting from / to java types
These are universal data structures. Virtually all modern programming languages support them in one form or another. It makes sense that a data format that is interchangable with programming languages also be based on these structures
Integration : today there are many frameworks that exchange data in the JSon format , now openspaces is in that list

More information can be found here http://www.json.org/