The question's about lyrics in "Still Fallin" sung by Hunter Hayes.
The first line of the song is
You'd think for all the days I've known you (that) I would have you memorized by now.
The reason why I put parentheses on 'that' is although the lyrics says it has 'that' in it, I don't find it grammatically correct. Am I right? or wrong?
Plus, I've been wondering what does it mean by
I would have you memorized by now.
Does it have the same meaning as "I would have memorized every details about you."?