The data modeler is responsible for getting approval of the logical data model from the business area experts and then works with the DBA to transition the logical model to the physical model. To create a good quality database design, the database administrator reviews the logi-cal model to select technology appropriate keys, create indexes, detail data types, and build referential integrity to protect the data values. The database administrator may de-normalize the database for efficiency. DBA's also are responsible for writing stored procedures, triggers, maintaining referential integrity, and monitoring database performance. Reviewing the information in the table below, one could gloss over the importance of the differences between the models.
Many people carelessly interchange the word entity with the word table.
However, the distinction is significant. An entity represents a set of persons, things, or concepts that are important to the business. The difference is the link to technology. Also consider the difference between a unique identifier in the logical model and a primary key in the physical model. This is an important business require-ment and must be captured as such.