create a ERD and provide DDL, DML for REST API format

A university need a database design to organize their data. We as developers start to help them. We start by designing data for student and lecturer. They have a name and study/work for a specific major . University also need to know the year when students joined and graduated. We can put null value if the student has not graduated yet. After that, we need to design how students take their studies. First, a lecturer can teach more than one subject. We always put a new record in subject table for every semester because sometimes the lecturer who teaches the subject may change. Then, students can choose the subjects they want. In this case, only approved requests are stored in the database. Lets put that on table named study with a score column to save their scores for later. We put null if the study has not scored yet.