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A database administrator (DBA) manages computer databases. [1] The role may include capacity planning , installation , configuration , database design , migration , performance monitoring, security , troubleshooting , as well as backup and data recovery .
Query rewriting is a typically automatic transformation that takes a set of database tables, views, and/or queries, usually indices, often gathered data and query statistics, and other metadata, and yields a set of different queries, which produce the same results but execute with better performance (for example, faster, or with lower memory use). [1]
Data Director users must log in with their database-specific credentials to view the database, its entities, and its data or to perform database management tasks. Database administrators and application developers can manage databases only if they have appropriate permissions and roles granted to them by the organization administrator.
[4] Queries allow the user to describe desired data, leaving the database management system (DBMS) to carry out planning, optimizing, and performing the physical operations necessary to produce that result as it chooses. A query includes a list of columns to include in the final result, normally immediately following the SELECT keyword.
The database schema is the structure of a database described in a formal language supported typically by a relational database management system (RDBMS). The term " schema " refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases ).
In modern management usage, the term data is increasingly replaced by information or even knowledge in a non-technical context. Thus data management has become information management or knowledge management. This trend obscures the raw data processing and renders interpretation implicit. The distinction between data and derived value is ...
The relational model was introduced by E.F. Codd in 1970 [2] as a way to make database management systems more independent of any particular application. It is a mathematical model defined in terms of predicate logic and set theory , and implementations of it have been used by mainframe, midrange and microcomputer systems.
The name is a three-letter acronym for DataBase Manager, and can also refer to the family of database engines with APIs and features derived from the original dbm. The dbm library stores arbitrary data by use of a single key (a primary key ) in fixed-size buckets and uses hashing techniques to enable fast retrieval of the data by key.