Improve duplicate endpoints error message

[nguyenalter]

Summary

• Improve duplicate endpoints error message
• With this SQL code (MySQL):

  CREATE TABLE score_subject (
    subject_id INT,
    score_id INT,
    PRIMARY KEY (subject_id, score_id)
  );
  
  CREATE TABLE student (
    id INT PRIMARY KEY,
    first_name VARCHAR(100) NOT NULL,
    last_name VARCHAR(100) NOT NULL,
    score_id INT,
    subject_id INT,
    CONSTRAINT fk_student_score_subject_id
    FOREIGN KEY (subject_id, score_id) REFERENCES score_subject(subject_id, score_id)
  );
  
  ALTER TABLE student ADD FOREIGN KEY (subject_id, score_id) REFERENCES score_subject(subject_id, score_id);

  • The error message raises by CLI: Reference with same endpoints duplicated.
  • The improved error message: Reference with the same endpoints already exists: "student"("subject_id", "score_id") references "score_subject"("subject_id", "score_id")

Issue

• Make duplicated reference error more clear #230
• https://community.dbdiagram.io/t/importing-from-mysql-file/762/3

Lasting Changes (Technical)

• Improve duplicate endpoints error message: adding schema, table and field information to the error message for more clarification

Checklist

Please check directly on the box once each of these are done

• Documentation (if necessary)
• Tests (integration test/unit test)
• Integration Tests Passed
• Code Review

[NQPhuc]

LGTM!