Health Data Clinic - Book 4: Enhanced ER (EER) Modeling

Some things in a clinic come in families. A staff member may be a physician, a nurse or a technician; a patient may be an inpatient or an outpatient. Enhanced ER modeling is how you draw that shared parent, and this book takes you from plain ER into it. You learn superclasses and subclasses, inheritance, and the difference between specialization, which splits a general type into specific ones, and generalization, which works the other way. Then come the constraints that keep a hierarchy honest: disjoint against overlapping, total against partial, and the category or union type. The EER symbols are laid out so you can read any hierarchy on sight. Three mapping strategies follow, a single table, a table per subclass, and concrete classes only, with a clear guide to choosing between them, healthcare patterns worth copying, the mistakes people repeatedly make, and a final check on the hierarchy you have drawn.

Twenty-five A4 pages, in full color. Written in short sentences and plain English, for readers whose first language is not English and clearer for everyone else because of it.

Every query in this book was run against a live database before the page was printed, so the result you read is the result you get. Instant PDF download. By M.R. Sterling.