image/svg+xml "ca" "at" "t " Token Posting list PGroonga 10:1,20:4 10:2,20:1 20:2 cat Query Tokenize AND cat at car 10 20 Documents ID Text 10 Result " c" "ar" 20:3 20:5 Search Appearance position check(Point: In PGroonga) "ca","at" 1 2