Results for: l-and-r-schemas

Explain the difference of internal external and conceptual schemas how are these schema layers related to the concept of logical and physical data independence?

External schemas allows data access to be customized (and authorized) at the level of individual users or groups of users. Conceptual (logical) schemas describes all the data that is actually stored in the database. While there are several views for… Full Answer

Why are schemas useful?

Schemas allow us to take cognitive shortcuts and make decisions without much conscious thought. The use of a schema keeps the mind from working too hard and lets people multitask. Full Answer