1 / 1

Effective Subtype Implementation in Database Design

Learn how to represent subtypes with key attributes and additional specific attributes, using (n+1)-relation, (n)-relation, or 1-relation solutions. Example: Manager (EmpNo, OfficeNo...)

jaime-carpenter
Download Presentation

Effective Subtype Implementation in Database Design

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Umsetzung von Untertypen Darstellung eines Untertyps durch das Schlüsselattribut des Obertyps zusammen mit beliebigen zusätzlichen Attributen, die den Untertyp spezifizieren ((n+1)-Relationen-Lösung) Darstellung eines Untertyps durch alle Attribute des Ober-typs zusammen mit beliebigen zusätzlichen Attributen, die den Untertyp spezifizieren (n-Relationen-Lösung) Darstellung eines Untertyps durch Vereinigung seiner Attribute mit den Attributen des Obertyps (1-Relation-Lösung) Beispiel:Führungskraft (MNr, BüroNr, ... )

More Related