You have no limit for the data. When your options data is in a dataset options.t8, put the greeks and other data in a parallel dataset greeks.t99. To retrieve all greeks that belong to the current options chain, use dataFind() with the current date. It returns the row with the additional data for the first contract of the chain. The other contracts are in the next rows.

We will make this easier in a future version by storing the dataset row number of a found contract.