SELECT stuid, SUM(hours_played) FROM plays_games GROUP BY stuid
Show all student ids and the number of hours played.
CREATE TABLE video_games (
    gameid number,
    gname text,
    gtype text
)

CREATE TABLE sportsinfo (
    stuid number,
    sportname text,
    hoursperweek number,
    gamesplayed number,
    onscholarship text
)

CREATE TABLE plays_games (
    stuid number,
    gameid number,
    hours_played number
)

CREATE TABLE student (
    stuid number,
    lname text,
    fname text,
    age number,
    sex text,
    major number,
    advisor number,
    city_code text
)