Data modeling reading for class 04

Conceptually data modeling is the practice of taking a set of data and defining a strict set of rules for what the data can contain and what relations it has to other data in your model.

There are three main types of data modeling.

The physical data model is a schema for how the data will physically be stored. This often is represented in the form of tables and relationship lines representing foreign keys.

The conceptual data model is a high level view of what is going on with the data. This is usually focused on a user based perspective. This type of data model usually does not have technical attributes.

The logical data model is a type of data model that has the most fully fleshed out technical specifications. It will often include primary keys, foreign keys, normalized tables, and relationships between the tables. This type of data model will also have restrictions on the types of data that can be in a table such as varchar.