TODO in database.service.ts

Hi
Thanks for publishing thi basic NestJS setup.
I have noticed this TODO entry in database.service.ts:
// TODO: reuse the same client + connection limit
While "connection limit" tells it all (I suppose), I'd like to ask what do you mean by "reuse the same client"?
Isn't it reusable already by injecting in every "functional" service?

TIA
Marcin