Queries

Query To search a database we use a query. A query selects only those records that meet certain conditions (or criteria ). There are three general methods for posing queries: Choosing parameters from a menu : In this method, the database system presents a list of parameters from which you can choose. This is perhaps the easiest way to pose a query because the menus guide you, but it is also the least flexible. Query by example (QBE): In this method, the system presents a blank record and lets you specify the fields and values that define the query. Query language : Many database systems require you to make requests for information in the form of a stylized query that must be written in a special [|//query language//]. This is the most complex method because it forces you to learn a specialized language, but it is also the most powerful