+ FOREIGN KEY(id_group) REFERENCES groups(id)
+);
+
+create table attachments (
+ id INTEGER primary key autoincrement,
+ url TEXT not null,
+ id_vote INTEGER not null,
+ FOREIGN KEY(id_vote) REFERENCES vote(id)
+);
+
+create table choices (
+ id INTEGER primary key autoincrement,
+ name TEXT not null,
+ id_vote INTEGER not null,
+ FOREIGN KEY(id_vote) REFERENCES vote(id)
+);
+
+create table user_choice (
+ id_user INTEGER,
+ id_choice INTEGER,
+ weight INTEGER,
+ FOREIGN KEY(id_user) REFERENCES users(id),
+ FOREIGN KEY(id_choice) REFERENCES choices(id),
+ PRIMARY KEY(id_user, id_choice)