For example, the following diagram states the manufacturer of "wine" twice: once as a related entity and once as an attribute. As well as wasting space and creating clutter, it also encourages inconsistency. Redundancy is when you say the same thing twice. Connecting relationships to each other.ฤก.Including weak entity sets when a strong one will suffice.Overusing composite, multivalued, and derived attributes.Using arrows as connectors (unless it's indicating a cardinality of "one").Saying the same things twice with redundant representations.In addition to creating a clean, readable diagram, you should avoid any of the following poor practices: In this week's post, I show you how not to make one. In my previous blog post, I introduced you to the basics of E-R diagram creation. Tips to guide you in your E-R diagram design.5 things not to include in your diagram.Good E-R diagrams capture core components of an enterprise.
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