Weight of the audio file in the soundbank

Question

Hi,
I have a simple question:
For example, I have a 15 minute piece of music. If I do a 3 second sample in Wwise and the rest I don't need. When I generate the Soundbank, do I only need the 3 seconds or the whole song (the 15 minutes)? It's mainly for a question of weight

Well, my example is a little bit oversized, but it's just to know

Even if I think I have my idea about it, I still ask

Thanks