Chemical composition of the Sgr stream. Top panel: [α/M] against [Fe/H] of the stream with APOGEE data (in the background, the same but for the whole APOGEE sample). Bottom panel: Normalised metallicity distribution function for the trailing (), core (), and leading () parts (top, middle, and bottom, respectively) in bins of 0.2 dex, shifted vertically for clarity. Top right part of each panel we show the number of stars. All three samples, LAMOST, APOGEE, and SEGUE, agree that the leading arm is more metal poor than the trailing.