to request for information from a database. 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.
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