username should be unique in database

[abdhalees]

since you're checking for the username to not be used before in your validation file

twitter/src/validation.js

Line 68 in 6cf790b

signupRet.msg = 'username is already a member';

maybe it would be better to make it a constraint in your schema.

twitter/src/database/db_build.sql

Line 7 in 6cf790b

username VARCHAR(100) NOT NULL,