Two dimensional array with string type keys

[rothe]

Hi!
I am making query to database and I am wondering is it possible to store data into 2 dim array where the keys are not integers but strings. I have tried IStringMap but executing data.Add(key value) requires that "value" must be str type (not another IStringMap). For example my array should be like:
[alpha][PROD_ID]=ab123
[alpha][PROD_NAME]=name_123
[alpha][PROD_QTY]=3
[beta][PROD_ID]=bb456
[beta][PROD_NAME]=name_456
[beta][PROD_QTY]=5

I couldn't find any format to store such array. Maybe it is even possible to ask values like:
value=data[alpha][PROD_QTY] ?

Thanks