Design a Basic Music Streaming System (Spotify-like)

Requirements: Design a basic Spotify-like music player system supporting: maintaining a playlist, adding a song, and searching for a song.

Design: Choose a DB (relational for structured song/playlist/user relationships vs. a search-optimized store for song search), define a schema (Users, Songs, Playlists, PlaylistSongs join table), and discuss normalization (separating Songs from PlaylistSongs to avoid duplicate song metadata) vs. denormalization for fast playlist-read queries (e.g. embedding minimal song metadata directly in playlist-read views to avoid joins at read time).