A _________ is a description of only that portion of the database pertinent to a particular user’s needs.

A view is a description of only that portion of the database pertinent to a particular user’s needs. In the context of databases, a view is a virtual table that is based on the result set of a SQL query. It contains rows and columns just like a real table, but the data is generated dynamically based on the underlying tables when the view is queried.

Views are instrumental for several reasons. They can simplify complex queries, provide a secure way to present data to users by exposing only necessary columns and rows, and can also encapsulate complex calculations. For instance, instead of giving a user access to an entire table, a database administrator can create a view that only shows the data relevant to the user, thus enhancing security and usability. Moreover, views can help in maintaining data integrity, as they can provide a consistent representation of the underlying data, even if the data in the base tables changes.