SQLite: Preventing Duplicate Rows

Question

CREATE TABLE Permission ( 
    permissionID INTEGER PRIMARY KEY UNIQUE,
    user         INTEGER
    location     INTEGER 
);

I don\'t want to have

Answer 1

CREATE TABLE Permission ( 
    permissionID INTEGER PRIMARY KEY UNIQUE,
    user         INTEGER,
    location     INTEGER 
);
CREATE UNIQUE INDEX user_location ON Permission (user,location);