Data retrieval means obtaining data from a

Database Management System In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases span ...

(DBMS) such as

ODBMS An object database or object-oriented database is a database management system in which information is represented in the form of objects as used in object-oriented programming. Object databases are different from relational databases which are ...

. In this case, it is considered that data is represented in a structured way, and there is no

ambiguity Ambiguity is the type of meaning in which a phrase, statement or resolution is not explicitly defined, making several interpretations plausible. A common aspect of ambiguity is uncertainty. It is thus an attribute of any idea or statement w ...

in data. In order to retrieve the desired data the user present a set of criteria by a query. Then the DBMS selects the demanded data from the database. The retrieved data may be stored in a file, printed, or viewed on the screen. A ''query language'', such as '' Structured Query Language'' (SQL), is used to prepare the queries. SQL is an

American National Standards Institute The American National Standards Institute (ANSI ) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organ ...

(ANSI) standardized query language developed specifically to write database queries. Each DBMS may have its own language, but most relational .

How the data is presented

Reports A report is a document that presents information in an organized format for a specific audience and purpose. Although summaries of reports may be delivered orally, complete reports are almost always in the form of written documents. Usage In ...

and queries are the two primary forms of the retrieved data from a database. There are some overlaps between them, but queries generally select a relatively small portion of the database, while reports show larger amounts of data. Queries also present the data in a standard format and usually display it on the monitor; whereas reports allow formatting of the output however you like and is normally printed. Reports are designed using a report generator built into the DBMS.

References

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External links

SQL Statements
SQL Statements Tutorial
SQL Tutorial at W3Schools
{{DEFAULTSORT:Data Retrieval Database management systems Relational database management systems

How the data is presented

See also

References

External links