I am creating ERD following some database design requirements.

This specific part on the ERD is what I am trying to represent. enter image description here

I made the MANAGEMENT entity because it's related to DATE_ACCEPTANCE, which is about managers working term (when it's started, who is the manager at a specific time).

I'm currently not sure about the relation between MANAGEMENT and 2 other entities in this ERD as it might affect the conversion to relational model.

  • it would be enough to add the two columns of management zo the employee table, also why is there a relationship between management dan department without any column
    – nbk
    Mar 1 at 10:53
  • To @nbk : Are you talking about the FKs that specify the relationship? If yes, I will add them in the relational model step. Secondly, the requirement is actually on the DEPARTMENTS, that is, each department must have a manager and his/her date of acceptance. The MANAGE recursive relationship has nothing to do with that requirement I think (like supervising).
    – Albert
    Mar 1 at 11:22
  • you have a relations hip between management and department but neither manager code in department nor department code in management
    – nbk
    Mar 1 at 11:24
  • To @nbk : I believe when I translate this into relational model, MANAGER_CODE would be add to DEPARTMENTS as FK. At first, I let MANAGER_CODE and DATE_ACCEPTANCE be in DEPARTMENTS. Then my lecturer advised me to establish another relationship between DEPARTMENTS and EMPLOYEES, that's why we are here. Do you find my question too confusing? Would it be better if I add full DB requirements and full of my current ERD to this question?
    – Albert
    Mar 1 at 11:35
  • so doesn't sql work, you need column(s) that references the other tables prmary key or unique/ index constaraint
    – nbk
    Mar 1 at 11:49


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