That was an attempt to say (without resorting to Big Oh notation) that the data structures and algorithms we're working on provide O(1) lookups that take a fixed amount of time regardless of the reference / dataset size. Does that make more sense?
I understand what it means, but what I don't understand, and was curious about, is how you can achieve constant-time searching or the dataset. I started with the assumption that you're doing approximate matches, is this correct?
Ah – well to clarify, we're performing exact match lookups on individual k-mers (k-length genetic strings), and then computing a classification result from those exact searches.