Data retrieval means obtaining data from a
Database Management System (DBMS) such as
ODBMS. In this case, it is considered that data is represented in a
structured
Structuring, also known as smurfing in banking jargon, is the practice of executing financial transactions such as making bank deposits in a specific pattern, calculated to avoid triggering financial institutions to file reports required by law ...
way, and there is no
ambiguity 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 (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.
See also
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Database model
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Data maintenance
Data management comprises all disciplines related to handling data as a valuable resource.
Concept
The concept of data management arose in the 1980s as technology moved from sequential processing (first punched cards, then magnetic tape) to ...
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Relational database
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Query by Example
Query by Example (QBE) is a database query language for relational databases. It was devised by Moshé M. Zloof at IBM Research during the mid-1970s, in parallel to the development of SQL. It is the first graphical query language, using visual ...
References
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External links
SQL StatementsSQL Statements Tutorial
SQL Tutorial at W3Schools
{{DEFAULTSORT:Data Retrieval
Database management systems
Relational database management systems