Hi folks, I wanted to ask you something I have been dealing with for as long as I have learned music theory: when is the point that you simply learn stuff by heart?

For example: I could not imagine writing out all keys in order to learn which notes a contained in them. But I learned all notes in all diatonic 7th chords by simply using flashcards. How am I to „practices“ my way into knowing what notes makes up a Dminor7?

Whats your experience with that? Where do you draw the line?